Sensor Cleaning Tips for DSLR Camera

How to minimize dust:-

1. Switch off camera before changing lenses. This reduces charge on sensor which helps reduce dust attraction.
2. Hold camera downwards when changing lenses to stop heavier dust floating into the chamber.
3. Hold the lenses downwards after removing from camera for the same reason.
4. Put a dust cap on lens as soon as not in use.
5. Keep camera bag clean if you keep lenses in your camera bag.
6. If you keep lens caps in your pocket then do not attach them to body caps without dusting them first as this will eventually transfer lint and dust in your pocket to the sensor.
7. If you keep lenses in your pocket during a shoot then clean your pockets first.
8. Generally keep your gear clean. I wipe my gear clean with a damp cloth after each trip.


How to check if your full frame sensor is dirty:-

Please note that this test may make you unhappy! It may well be that you have a dusty sensor but it has made no difference to your shooting and now you find out you obsessively try to clean the sensor.

I find I cannot actually see the dust on the sensor and this is why a photograph is necessary. Dust tends to show up as small dark round patches in photographs. The smaller the aperture you shoot at the more they become obvious. Also they tend only to show up on light backgrounds. This means some people may not see them at all whilst others will. For example landscape photographers usually have the sky in the top part of the frame where dust will show up if in this area of the sensor.

1. Stick on a telephoto lens. Select f22 aperture. Select the maximum telephoto if a zoom lens. Focus to infinity.
2. Point the camera at a white wall. If no white wall try a clean piece of paper.
3. Let the camera select an auto shutter speed. It does not matter if you have camera shake, 0.5 to 2 seconds is fine. The idea is to have a blank subject and have the camera exposure meter turn this medium grey.
4. Transfer the photo to your computer. View the photo at around 1600 x 1200. You should see any dust and marks easily.

Please don't panic. Remember your camera is probably cleaner than most other peoples! Reference for good cleaning information:-


Recommended sensor cleaning:-

1. Wet clean

You should use wet cleaning when you have smears or blobs on the sensor. Smears are caused by skin oils, using too much cleaning fluid, using cheaper quality cleaning fluid, and by grease and oils sometimes coming from elsewhere in the camera.

I have found the trick with the 5D is to clean with two sensor swabs instead of only one and also clean carefully at the edges of the sensor.

On a cropped sensor you do not normally have to worry about the edges because the swab will overlap the sensor. With the 5D the sensor is fairly flush with the chamber wall making it hard to clean.

Because the 5D sensor is larger relative to the chamber you need to clean the edges. This is achieved by ensuring you swipe the edges, one edge on each sweep.

I contacted various sensor cleaning companies and I was advised that they use the 'Wet' method that is a swab and alcohol or methanol fluid.

Although an expensive method it is very useful to get the sensor spotless the first time it is used.

I found SensorSwabs from Photographic Solutions a good method used with Eclipse fluid also by Photographic Solutions. There are also other companies offering similar solutions. If these are too expensive then these can be made up more cheaply using the 'Copperhill' method by using 'PecPads' wrapped around a spatula.

SensorSwabs are expensive because they are produced in a 'Clean Room' free from airborne contaminates. Please note that Photographic Solutions do not promote the 'Copper Hill' method and say that their SensorSwabs use another material other than PecPads. However as SensorSwabs are so expensive about $5 each, some users prefer to roll their own.

Photographic Solutions guarantees that your sensor will not be damaged by using sensor swabs. They now also recommend use of the original Eclipse fluid on their website and not the new E2 Eclipse fluid.

Please note that Canon only recommend blowing, however with this guarantee from Photographic Solutions I am happy to use this method.

Also note that Canon may offer a free cleaning during the first year so do try this as an option.


A. Preparation

To start select sensor cleaning from the camera menu. This lifts up the mirror giving access to the sensor.

I hold the camera up and tilt the camera down so as to avoid collecting dust while cleaning.

Warning: Do not switch camera off accidentally whist cleaning or allow batteries to become dead, otherwise the mirror may flip down and it may be damaged.

Do not believe Canon technical support when they tell you that the SENSOR CLEANING menu selection will self-clean the camera. This is nonsense! All the menu selection does is lift up the mirror and turn off the sensor.


B. The Edges

The edges of the sensor are very hard to clean on the 5D and in fact many outlets offering sensor cleaning charge more for the full frame sensor. In fact some go so far as to take the camera apart to more easily get at the sensor.

Place only 2 drops (3 at most) of Eclipse fluid on a SensorSwab. Place on the tip which will be in contact with the sensor. More will cause streaking.

First use a horizontal sweep LEFT to RIGHT ensuring top edge is swiped. Then use same swab tilted the other way and use a horizontal sweep RIGHT to LEFT ensuring the bottom edge is swiped.

Second use a new swab and give the sensor a vertical sweep UP to DOWN ensuring left edge is swiped. Then use same swab tilted the other way and use a vertical sweep DOWN to UP ensuring the right edge is swiped.

The first time you clean the sensor yourself you may like to use a third swipe horizontally either using a new swab or reusing the second swab once more.

You may have heard from suppliers that the extreme left and right side edges of the swab do not clean efficiently because the material is not supported inside the swab. This is incorrect and it is actually these edges that are needed to clean the edges of the sensor in a full frame sensor. In a cropped sensor these SensorSwab edges float over the edge of the sensor and only touch air so it become less relevant on a cropped sensor compared to a full frame sensor.

To ensure the edges are cleaned you may find it useful to twist the swab slightly (around the vertical axis of the swab) during the sweep to ensure that the one corner of the swab is slightly forward at the end of the sweep and touches the edge and corner of the sensor. Remember the trick is to lift up impurities at the edges and not to push it into the corners and sides where it is hard to access.

I keep swabs and the eclipse fluid in a small wallet that came from Photographic Solutions.


C. Check

I then test the cleanliness of the lens. See 'How to check if your full frame sensor is dirty' above. I sometimes find one or two dust particles have arrived during cleaning or immediately afterward. In this case I simply give the sensor a blow as described below. Often a second blow is necessary if the first blow did not do the trick.

When blowing remember that the dust photograph is reversed left to right and inverted top to bottom in relation to the camera viewed from the back. So if for example you are looking at a speck on the top right of the photograph it will appear on the bottom left of the sensor when camera viewed from the back. This will appear on the bottom right if camera viewed from the front while actually cleaning. This is less necessary to know while swabbing as the whole sensor is cleaned when swabbing. With blowing you can concentrate where the actual dust is.


2. Large Blower.

For regular dust, and not smears, use a large hand blower.

This is recommended by Canon. Anything else may void their warranty.

I use the large black blower that came in a sensor cleaning kit from Lenspen. It has a small soft rubber snout to protect lenses and sensors and a double valve. The rubber part is four inches long and two inches diameter and the nozzle is an extra two inches.

To start select sensor cleaning from the camera menu. This lifts up the mirror giving access to the sensor. I tilt the camera down so as to avoid collecting dust while cleaning.

I stick the tip halfway into the chamber and blow by squeezing. I make sure not to touch the sensor.

I keep it in the soft leather case that came from Lenspen. I keep a smaller blower handy in the camera bag to blow dust away from the lens and lens caps.

I have found that blowing removes all loose dust. Sometimes I have to blow twice checking between each time.


3. Lenspen

I have tried Lenspen SensorKlear. I found it is excellent for dust but hopeless for removing the last of smears and grease etc.

I have decided not to use this method as the Sensorklear tip is not designed to be cleaned by the user. My concern is that particles from a previous cleaning may be rubbed over the sensor. Instead the dust is removed by twisting the closed cap which moves the chamois on the tip onto a sponge in the cap and reintroduces non-liquid carbon compound to the chamois. The instructions say use only 50 times then dispose. However the Lenspen is simple to use and is marvelous for cleaning lenses.


4. Brushes.

This method works. The method uses positively charged brush hairs to gently lift dust by being in contact with the sensor.

I bought a sensor brush from Copper hill Images called SensorSweep II. This works by blowing a small jet of air, using the supplied battery operated blower, through the bristles of the brush. Note it is not the power of the blowing that increases the charge, but the bristles rubbing against each other building up static electricity, rather like rubbing a balloon on a jersey.

The brushes with many hairs work best. The Arctic Butterfly from Visible Dust seems a reasonable method on the go, however it has less bristles than dedicated brushes. In fact some cleaning service companies recommend this method to customers between their cleaning as it is fairly easy to use even for people afraid of cleaning their sensors.

I must admit as the blower method is working for me I have not bothered to continue the brush methods.


5. SpeckGrabber

This is a small stick with a man made washable permanently sticky end. You can lift off difficult to remove items without rubbing the sensor. You simply press down and lift. This was invented for mirrors and focus screens and lenses. It works OK on sensors provided it is kept clean. It comes in a small tube which I keep in a wallet with the sensor swabs. You can clean with soap and water or Eclipse fluid and a PecPad.


6. Cotton buds

I tried these and found they introduce specks to the sensor. Reference for good cleaning information:-

http://www.cleaningdigitalcameras.com
http://www.kinetronics.com
http://www.visibledust.com
http://www.kinetronics.com
http://www.lenspen.com/403/377/

In the next generation 5D maybe in 2008 I hope the chamber walls will be made slightly larger so that the sensor becomes easier to clean. They may also invent some method to prevent the charge on the sensor that attracts dust in the first place.

Shots Underwater

Memories are created just anywhere. And when I say anywhere, I mean that memories are even created underwater – so the creation of underwater digital camera.
An underwater digital camera is not just used to captivate underwater memories; some professional marine photographers also use underwater digital cameras in their business. Even marine biologists and scientists use underwater digital cameras to capture marine life and thus be able to study the life and properties of the marine life. But I think it is good to assume that you, my viewer, are neither a marine scientist nor a professional photographer. Like me, you are just some photo freak who wants to capture underwater moments and just cant figure out how without breaking your cameras.

Please bear in mind that even waterproof cameras cannot endure underwater photography. To be waterproof is to withstand the water in certain levels, immersion in under the water to get the perfect shot is like throwing it out of the window expecting a pick-up truck to pass by and run over it.

Now if you’re really into using an underwater digital camera to capture those wacky and funny moments underwater, I advise that you purchase specialty cameras.

There are seldom underwater digital cameras, as cameras are electronic and cannot withstand water and water pressure. The closest electronics has ever got to producing underwater digital cameras are producing underwater casings for digital cameras. These casing will turn your conventional digital camera into an underwater digital camera.

If you are shooting with your underwater digital camera, you need to observe a few things to help you come up with the best images underwater.

Keeping in mind that as you go deeper underwater, light diffuses. This means that your underwater digital camera will develop images darker than those images you took while on land – this is due to the light diffusion the red spectrum appears darker. To deflect this, use white balance come up with natural colours. Likewise, pictures taken underwater will come up larger than pictures taken on land with the same zoom effect. Make sure to check your underwater digital camera’s viewfinder to check the right picture angle and size that you want.

An underwater digital camera with its built-in flash will bring about marine show phenomenon. It is a phenomenon wherein your pictures appear as blurry and with white particles floating above it, to avoid this phenomenon it is advisable to use external flash for your underwater digital camera.

Prior to using your underwater digital camera, submerge the camera in the water first for several seconds then check if there are leaks through the case. Be sure that no grain of sand or piece of hair is slipped in between the seal to be sure that water will not penetrate the case and hence wet your camera in the process. It is also recommended to put silica gel or two inside the case of your underwater digital camera as long as they don’t disturb the camera’s operation.

Most underwater digital cameras accompany optional lenses. Don’t be afraid to add these lenses to your underwater digital camera kit. Macro lenses will help you capture small things without getting too close and galvanizing your subject.

Besides, remember to always wash of salt when you’ve used it under seawater. If the salts are not washed off, in time they will crystallize; act as sands and cause leaks for your camera case. If sands seem to get into the case, they are better washed off with streams of water.

History of Photography by Timeline

· 1900: Kodak Brownie box roll-film camera introduced.

· 1902: Alfred Stieglitz organizes "Photo Secessionist" show in New York City

· 1906: Availability of panchromatic black and white film and therefore high quality color separation color photography. J.P. Morgan finances Edward Curtis to document the traditional culture of the North American Indian.

· 1907: First commercial color film, the Autochrome plates, manufactured by Lumiere brothers in France

· 1909: Lewis Hine hired by US National Child Labor Committee to photograph children working mills.

· 1914: Oscar Barnack, employed by German microscope manufacturer Leitz, develops camera using the modern 24x36mm frame and sprocketed 35mm movie film.

· 1917: Nippon Kogaku K.K., which will eventually become Nikon, established in Tokyo.

· 1921: Man Ray begins making photograms ("rayographs") by placing objects on photographic paper and exposing the shadow cast by a distant light bulb; Eugegrave;ne Atget, aged 64, assigned to photograph the brothels of Paris

· 1924: Leitz markets a derivative of Barnack's camera commercially as the "Leica", the first high quality 35mm camera.

· 1925: André Kertész moves from his native Hungary to Paris, where he begins an 11-year project photographing street life

· 1928: Albert Renger-Patzsch publishes The World is Beautiful, close-ups emphasizing the form of natural and man-made objects; Rollei introduces the Rolleiflex twin-lens reflex producing a 6x6 cm image on rollfilm.; Karl Blossfeldt publishes Art Forms in Nature

· 1931: Development of strobe photography by Harold ("Doc") Edgerton at MIT

· 1932: Inception of Technicolor for movies, where three black and white negatives were made in the same camera under different filters; Ansel Adams, Imogen Cunningham, Willard Van Dyke, Edward Weston, et al, form Group f/64 dedicated to "straight photographic thought and production".; Henri Cartier-Bresson buys a Leica and begins a 60-year career photographing people; On March 14, George Eastman, aged 77, writes suicide note--"My work is done. Why wait?"--and shoots himself.

· 1933: Brassaï publishes Paris de nuit

· 1934: Fuji Photo Film founded. By 1938, Fuji is making cameras and lenses in addition to film.

· 1935: Farm Security Administration hires Roy Stryker to run a historical section. Stryker would hire Walker Evans, Dorothea Lange, Arthur Rothstein, et al. to photograph rural hardships over the next six years. Roman Vishniac begins his project of the soon-to-be-killed-by-their-neighbors Jews of Central and Eastern Europe.

· 1936: Development of Kodachrome, the first color multi-layered color film; development of Exakta, pioneering 35mm single-lens reflex (SLR) camera

· World War II:

• Development of multi-layer color negative films
• Margaret Bourke-White, Robert Capa, Carl Mydans, and W. Eugene Smith cover the war for LIFE magazine

· 1947: Henri Cartier-Bresson, Robert Capa, and David Seymour start the photographer-owned Magnum picture agency

· 1948: Hasselblad in Sweden offers its first medium-format SLR for commercial sale; Pentax in Japan introduces the automatic diaphragm; Polaroid sells instant black and white film

· 1949: East German Zeiss develops the Contax S, first SLR with an unreversed image in a pentaprism viewfinder

· 1955: Edward Steichen curates Family of Man exhibit at New York's Museum of Modern Art

· 1959: Nikon F introduced.

· 1960: Garry Winogrand begins photographing women on the streets of New York City.

· 1963: First color instant film developed by Polaroid; Instamatic released by Kodak; first purpose-built underwater introduced, the Nikonos

· 1970: William Wegman begins photographing his Weimaraner, Man Ray.

· 1972: 110-format cameras introduced by Kodak with a 13x17mm frame

· 1973: C-41 color negative process introduced, replacing C-22

· 1975: Nicholas Nixon takes his first annual photograph of his wife and her sisters: "The Brown Sisters"; Steve Sasson at Kodak builds the first working CCD-based digital still camera

· 1976: First solo show of color photographs at the Museum of Modern Art, William Eggleston's Guide

· 1977: Cindy Sherman begins work on Untitled Film Stills, completed in 1980; Jan Groover begins exploring kitchen utensils

· 1978: Hiroshi Sugimoto begins work on seascapes.

· 1980: Elsa Dorfman begins making portraits with the 20x24" Polaroid.

· 1982: Sony demonstrates Mavica "still video" camera

· 1983: Kodak introduces disk camera, using an 8x11mm frame (the same as in the Minox spy camera)

· 1985: Minolta markets the world's first autofocus SLR system (called "Maxxum" in the US); In the American West by Richard Avedon

· 1988: Sally Mann begins publishing nude photos of her children

· 1987: The popular Canon EOS system introduced, with new all-electronic lens mount

· 1990: Adobe Photoshop released.

· 1991: Kodak DCS-100, first digital SLR, a modified Nikon F3

· 1992: Kodak introduces PhotoCD

· 1993: Founding of photo.net (this Web site), an early Internet online community; Sebastiao Salgado publishes Workers; Mary Ellen Mark publishes book documenting life in an Indian circus.

· 1995: Material World, by Peter Menzel published.

· 1997: Rob Silvers publishes Photomosaics

· 1999: Nikon D1 SLR, 2.74 megapixel for $6000, first ground-up DSLR design by a leading manufacturer.

· 2000: Camera phone introduced in Japan by Sharp/J-Phone

· 2001: Polaroid goes bankrupt

· 2003: Four-Thirds standard for compact digital SLRs introduced with the Olympus E-1; Canon Digital Rebel introduced for less than $1000

· 2004: Kodak ceases production of film cameras

· 2005: Canon EOS 5D, first consumer-priced full-frame digital SLR, with a 24x36mm CMOS sensor for $3000; Portraits by Rineke Dijkstra

Photography Exposure Basics

Five ways to use the Web—the world's largest photo gallery—to help you become a better photographer.

The Web has become an infinite photo gallery where we can show our best shots without stepping anywhere near a printer or photo lab. Increasingly, cyberspace is also where photographers go to learn technique and stay current. But browsers beware. "A lot of the advice and opinions you get on the Internet is just plain off," says photographer Bob Krist. "Anyone can put up a slick-looking website. I want to take my advice from someone who's making a living making pictures." With that in mind, Traveler asked some two dozen photographers—mostly professionals—to reveal their favorite hangouts in cyberspace.

1. Get Inspired

2. Gear Up

3. Learn the Ropes

4. Share Your Pictures

5. Order Prints



1. Get Inspired
Scrutinize the work of the masters and the pros.

"To improve my own photography," says Will van Overbeek, photographer and photo instructor, "I look at other photographers' photos and treat them like a puzzle. I ask myself, how was that done? Then I figure it out."

The Web is full of pictures worth scrutinizing. For starters, go to Masters of Photography, a plain-looking site displaying prints by a good sample of photographic greats, such as Ansel Adams, remembered for his large-format black-and-white pictures of Yosemite Valley; Margaret Bourke-White, the first female photojournalist to shoot for Life magazine; and Gordon Parks, a barrier-breaking African-American photographer.

A deeper source of historical imagery is the Library of Congress. Its website contains a million digitized photographs, including those by such masters as Dorothea Lange, who photographed scenes of the Great Depression for what became the Farm Security Administration, and Mathew Brady, the most famous photographer of the Civil War. Another treasure of classic photos—from the collections of New York's International Center of Photography and the George Eastman House—is browsable at a joint website.

Photography books, often of the coffee-table variety, have long been a source of inspiration to photographers, and now you can browse them on the Web.
"When a photographic project gets to the stage of being published in a book, typically that means the body of work is really solid," says photographer Justin Guariglia. "I look to photography books more than magazines to get inspired." His favorite publishers: Aperture Foundation, Twin Palms, Phaidon, and Nazraeli, not to mention National Geographic Books.

Photo-eye, an online photo store, lists some 14,000 photography books, as well as an online gallery of fine art photography by the likes of Steve McCurry, Robert Capa, and Imogen Cunningham. "Looking at photo books feeds ideas into your subconscious," Guariglia says, "and they come back when you're out photographing."

A source of inspiration unknown to many amateur photographers is photo agencies, or "stock houses," which sell images by thousands of contemporary photographers as well as from historic archives. Search their collections to see how the pros have already shot your upcoming travel destination—say, the Grand Canyon or Angkor Wat.

"Before going on a trip, I go to Corbis to see what a place looks like in general," says photographer Catherine Karnow. "That helps me narrow my shooting list." Corbis, founded in 1989 by Bill Gates, has some 70 million images. Other stock houses worth browsing are Getty Images, Magnum Photos, and VII. "For inspiration," says photographer David McLain, "I go to Aurora Photos more than any place else on the Web. It's the photo agency I belong to, and I always like to see the weekly features that are up as well as keep up with what my colleagues are shooting."

Another way the pros get inspiration and ideas is by visiting other shooters' own websites. "If you run across an interesting photographer," says van Overbeek, "say, in a magazine article, look for the photo credit, then google the name and check out the photographer's website." Adds photographer Farah Nosh: "My Web designer and I comb through hundreds of personal photography websites every time we are preparing an update for my own site."

Finally, realize that photography is part of the evolving digital media revolution, so keep an eye on "cutting-edge multimedia sites" like MediaStorm, says Daniel Westergren, Traveler's senior photo editor. Projects on the site converge photos, text, audio, and video.

2. Gear Up
View ratings and reviews before you buy.

When selecting a camera, there's no substitute for actually trying out the model you have in mind—but camera review websites come close. Start at Steve's Digicams, where photo buff Steve Sanders has been reviewing digital cameras since 1997. Reviews are indexed by brand and resolution. If you're looking to pick up an old two-megapixel camera on eBay, read the review here first—and view sample photos taken with the camera.

Another site that reviews pro models as well as entry-level cameras is CNET. "I like it because it not only has equipment reviews—often appearing just days after the product is released—but it also has user ratings and opinions," says photographer Kris LeBoutillier. "This gives me points to discuss with the salesman when I go to the camera store. You can also compare prices here."

Several professional photographers we interviewed recommended Digital Photography Review, founded in 1998. "It's very good for keeping you updated on new software as well as camera equipment," says photographer Palani Mohan. The site, written simply enough for novices and reviewing cameras at all price levels, claims to receive 18 million visitors a month.

Two companion sites that get the nod from some of the pros are Imaging Resource, for cameras, and SLR Gear for accessories, particularly lenses. "Both sites have no problem pointing out flaws and drawbacks in equipment," says photographer Raymond Gehman. "I found the honesty extremely helpful, especially when buying zoom lenses, which usually have great range, from good to bad, in quality."

At the high end of the technical scale is a site aimed squarely at professionals: Rob Galbraith, run by photojournalists. "This is the best site for pros who want to keep up with the latest hardware and software updates to the digital imaging and archiving tools we all use," says photographer Cotton Coulson. Of course, serious amateurs are welcome.

3. Learn the Ropes
Tap the collective know-how of the best shooters.

Once you've got a camera, you must learn how to use it. A font of basic knowledge is About, which covers everything from getting started in digital photography to how to photograph nudes. "For amateurs, I like Take Great Pictures," says photographer Michael Yamashita. Besides the basics, the site recently featured articles on underwater photography, shooting tornadoes, and photographing high-speed events like car races.

Go into more depth at the Luminous Landscape, maintained by pro shooter Michael Reichmann. Most notable are its columns by professionals and tutorials on subjects ranging from creating digital panoramas and understanding depth of field to night photography and matting prints.

Another site of use to professionals and amateurs alike is Fred Miranda, with articles, reviews, essays, and forums. The site, run by a freelance photographer, delves deeply into technique and equipment issues but still covers basics, including recent articles on "The way I shoot my flowers" and "Digital photography in the wilderness."

A site that helps take the fear out of flash is Strobist. "It has great ideas for lightweight flash and lighting solutions for photographers on the go," says Krist. Don't miss the primer called "Lighting 101."

Another good blog is the Online Photographer, "my favorite website," says Westergren, "where you can find discussions on all aspects of photography." The site tends toward advanced discussions but also links to fascinating projects such as "Life Vicarious: 448 days around the world," a photo documentary that commenced in September.

Check the website of your camera manufacturer for helpful resources. But also look at independent sites devoted to your brand, such as Nikonians, for Nikon users, and Photo Workshop, focusing on Canon equipment. Is it really necessary to steep yourself in all the technical aspects of photography? "Yes," says Guariglia. "You have to know how to work your camera really well before you can do anything."

4. Share Your Pictures
Post your photos online and let the world critique them.

Social-networking sites have exploded on the Web, and several focus on photography. More than just a gallery, these sites offer the chance to engage a community of serious and not-so-serious shooters. All the sites Traveler reviewed overwhelm you at first with the sheer volume of images posted. But the better sites impose some degree of order on their ever-growing collections.

Flickr, for example, is a site for the masses. It has a simple interface that hides a deep well of some 270 million images—all searchable by "tags," or keywords users have assigned to their own pictures. A search on "Grand Canyon," for example, brings up 67,730 photographs; "Golden Gate Bridge," 21,639. Order is further imposed by user groups indexed by subject, for example, "nature," "politics," "sports," and "food." The travel category alone has some 10,352 groups. Photos on Flickr can also be "geotagged," or assigned to map coordinates or addresses, so that others can find your pictures by clicking locations on a map of the world.

A site with similar tagging functionality but a more elegant interface is SmugMug. Here you can customize the look of your image collection with various thematic templates, such as "seasons," "holidays," and "sports," and then invite your friends to browse them for free. You pay $40 a year for the privilege.

Photo.net attempts to be comprehensive, offering not just photo sharing among its approximately 514,000 members, but also classified ads, equipment reviews, a learning center with tutorials, and discussion forums on such subjects as "lighting," "classical cameras," and "digital darkroom." Users post their images to a critique forum. The highest-rated shots appear as "top photos," so you can quickly view the best and skip the rest. "This site has a broad range of information," notes Westergren. "I particularly like the camera shopping forum, where users share good and bad experiences buying cameras."

Or, forgo the networking sites altogether and put up your own site, as the pros do. Some consumer-level image-editing software programs—such as Adobe Photoshop Elements—will automatically arrange your photos in a Web format. You then upload the files onto the Web space allotted to you by your own Internet service provider. Or pay extra to host a site through a domain registry like Network Solutions. "It's easier than a lot of people think," says van Overbeek. "Once you get the page up, circulate the URL among people you know who care about photography, and ask for their feedback."

5. Order prints
You can even get your photos in hardbound books.

Despite the wonders of showing your photos online, the Web will never fully replace the experience of viewing photographic prints. It does, however, provide a convenient way to buy them. Ordering prints from online photo labs is cheaper than printing your own at home and easier than dropping your files off at the drugstore—particularly if you have a broadband connection for fast uploads.

The leading online photo finishers, Snapfish, Kodak EasyShare Gallery, and Shutterfly, are all comparable in ease of use, delivery time (usually three or four days), and quality of printing. And all can also print your pictures on products other than paper, such as T-shirts and mouse pads. (Note: Macintosh users can order Kodak prints through their iPhoto application, but prices are lower at the Kodak website.)

You can also use the photo lab websites to share your photos. Simply send friends and family links to your online albums, where your guests can browse the pictures or purchase prints of their own. Even the pros, who generally get prints made at custom labs, use these sites to make hardbound books of their images quickly and easily. "It's the best product the online labs offer," notes Westergren.

One networking site, Fotki, offers enlargements that are considerably cheaper than the rest. Additional options include Wal-Mart, Clark Color Labs, and York Photo.

All online labs compete by price, with 4x6 prints going for as little as nine cents each. "At those prices," Westergren says, "even if the prints someday fade, you can just order more from your digital files, which stay fresh forever."

A Look at Urban Portraiture

In this post portrait photographer Christina Dickson tackles the topic of Urban Portraiture.

Within the photography world it is commonly expressed that the camera may be used to bridge the gap between people. In my own experience, I never fully realized this truth until this month.

This March, I have had the experience of becoming a street portraitist. Over a span of five weeks, I took to the streets of Portland for 3-5 hours every day, taking portraits of the homeless street community. I was not out to practice my portrait photography in a journalistic setting: my mission was personal.

I went out to answer a question that every portraitist must face:

Is it truly possible to capture the beauty of humanity even when one’s subject is a hardened, drug-addicted prostitute? Can I capture a portrait and cause my audience to see past the evidences of meth addiction, the multiple face piercings, and the glazed over eyes of drunkenness?

9 Lighting Types to Harness & Improve Your Photography

9 Lighting Types to Harness & Improve Your Photography

The following post on 9 Lighting Types is by San Francisco based photographer Jim M. Goldstein.

In my previous article “Make the Best of Bad Weather - 6 Challenges for Photographers” I noted how photography is all about the light. Sounds easy enough on the surface but as photographers we tend to be subject focused rather than light focused. What I mean by that is we’ll see something unique or different and focus on that rather than the lighting and resulting exposure needed to transform your subject. The right lighting can make or break an image setting the stage for others to see it as a snapshot or a photograph.

Just as finding and seeing a subject is challenging, so too is finding lighting conducive to taking dramatic photographs. The Golden Hour is always referenced as a great time to take photos, but its not the only time to take photos with dramatic lighting. Training your eye to see dramatic light and the different variations of it takes some self-training.

Side Lighting

As you might expect Side Lighting is when the lighting is coming from the side. This usually provides a great deal of contrast, can create long shadows and adds depth to the image. This type of lighting can add a dramatic flare to architectural and portraiture photography.

Back Lighting

Back lighting is when light is behind your subject and is directed at you and your camera. This type of lighting creates silhouettes quiet easily. Combined with certain atmospheric conditions such as fog or airborne dust you can get dramatic lighting effects.

Nikon

From Wikipedia, the free encyclopedia

Corporation TYO: 7731 Tokyo, Japan Imaging

Nikon Corporation 株式会社ニコン
Corporation TYO: 7731
Founded	Tokyo, Japan (1917)
Headquarters
Key people	Michio Kariya, President, CEO & COO
Imaging
Products	Precision equipment for the semiconductor industry, Digital imaging equipment and cameras, Microscopes, Optical measuring and inspection instruments, Lenses for glasses
Revenue	¥730.9 billion (Business year ending March 31, 2006)
Employees	16,758 (Consolidated, as of March 31, 2005)
Website	Nikon Global Gateway

Nikon Corporation (株式会社ニコン, Kabushiki-gaisha Nikon?) listen (help·info) (TYO: 7731), also known as Nikon or Nikon Corp., is a Japanese company specializing in optics and imaging. Its products include cameras, binoculars, microscopes, measurement instruments, and the steppers used in the photolithography steps of semiconductor fabrication. It was founded in 1917 as Nippon Kōgaku Kōgyō (日本光学工業株式会社 "Japan Optical Industries"); the company was renamed Nikon Corporation, after its cameras, in 1988. Nikon is one of the major companies of the Mitsubishi Group.

The name Nikon, which dates from 1946, is a merging of Nippon Kōgaku (日本光学: "Japan Optical") and an imitation of Zeiss Ikon. Nikon is pronounced differently around the world. The Japanese pronunciation of the name is /nikoɴ/, but in the United States people also use /ˈnaɪkɒn/ and /ˈnɪkɒn/.[1]

Among its famous products are Nikkor camera lenses (notably those designed for the company's own F-mount SLR cameras), Nikonos underwater cameras, the Nikon F-series of professional 135 film SLR cameras, and the Nikon D-series digital SLRs. Nikon has helped lead the transition to digital photography with both the Coolpix line of consumer and prosumer cameras as well as DSLR system cameras like the Nikon D300, D80, D60, and D40, and professional DSLRs including the D2 series and D3 cameras (see below).

Nikon's main competitors include Canon, Kodak, Sony, Pentax, Fujifilm and Olympus.

Nikon is the world's largest manufacturer of steppers and holds 44% share of the market.

Contents

History

Nikon Corporation was established in 1917 when three leading optical manufacturers merged to form a comprehensive, fully integrated optical company known as Nippon Kogaku Kokyo K.K. Over the next 60 years this growing company became a leading manufacturer of optical lenses and precision equipment used in cameras, binoculars, microscopes and inspection equipment. During World War II the company grew to 19 factories and 23,000 employees, supplying items such as binoculars, lenses, bomb sights and periscopes to the Japanese military. After the war it reverted to its civilian product range with a single factory. In 1948, the first camera with the Nikon brand was released, the Nikon I.[2]

Nikon lenses were popularised by the American photojournalist Douglas David Duncan's use at the time of the Korean War.[3] Fitting Nikon optics to his Leica rangefinder cameras produced high contrast negatives with very sharp resolution at the centre field.

Besides cameras, Nikon Corporation (Nikon) is recognized as a world leader in development and manufacturing of advanced optical and precision photolithography equipment. In 1980, the first stepper, the NSR-1010G, was produced in Japan. Since then, Nikon has introduced over 50 models of steppers and scanners for the production of semiconductors and liquid crystal displays. Nikon currently designs and manufactures precision equipment for use in semiconductor and liquid crystal display (LCD) fabrication, inspection, and measurement. Nikon also designs and manufactures visual imaging products including cameras; instruments such as microscopes; and other products such as chemical mechanical polishing (CMP) systems, binoculars, surveying instruments, eyewear, sport optics, and optical measuring and inspection equipment.

In 1982, Nikon Precision Inc. (NPI) was established in the United States. NPI is the North American sales and service arm specifically for Nikon Corporation's semiconductor photolithography equipment and is headquartered in Belmont, California. Fueled by a rapidly growing customer base, the company quickly expanded. In 1990, NPI opened its current headquarters and the facility now includes corporate offices, a fully equipped world-wide training center (WWTC), service operations, applications engineering, technology engineering, quality and reliability engineering, training, technical support, sales, and marketing for Nikon equipment serving the wafer, photomask, flat panel display, and thin-film magnetic head industries. Today, NPI is an industry leader in supplying and supporting advanced photolithography equipment used in the critical stages of semiconductor manufacturing.

Nikon Corporation also has research and development operations in the U.S. under Nikon Research Corporation of America (NRCA), which directly supports R&D efforts of the Precision Equipment Division in Kumagaya, Japan. By leveraging its strong and long-standing customer relationships, global brand recognition, and technological expertise, Nikon has positioned themselves to maintain their market leadership through its emphasis on leading-edge research and development and its ability to adapt its products to meet its customers' rapidly changing needs. The Nikon brand has recently slipped behind rival Canon in total sales. Nikon, once the industry leader, has found itself playing catch up to Canon, who was quicker to market with such innovations as image stabilization and piezo-electric (ultra sonic motor) focusing.

Today, Nikon Group Companies total nearly 17,000 employees worldwide.

In January 2006, Nikon announced it would stop making most of its film camera models and all of its large format lenses, and focus on digital models[4].

In late 2007, Nikon introduced the newest product in the Nikon Immersion Solution, the NSR-S610C, which uses a proprietary technology that eliminates bubbles, watermarks, and particles generated by immersion processing. This results in defect levels to occur at a rate similar to dry scanners.[citation needed]

In an effort to curb a thriving "grey market" for its cameras and lenses[citation needed], Nikon established a wholly owned subsidiary in India in September 2007, to handle India as well as the Middle East markets (comprising Saudi Arabia, Turkey, Iran, Bahrain, Israel, Oman, Qatar and the UAE). However the prices of the products imported legally are still higher than "grey markets" products.

Digital SLR

Definition of: DSLR

(Digital Single Lens Reflex) A digital still image camera that uses a single lens reflex (SLR) mechanism. Most professional cameras have always been single lens reflex cameras, although analog. Digital SLRs began to emerge in the early 1990s, but became very popular after the turn of the century. Following are the two major differences between DSLRs and standard digital cameras.

Removable Lenses
No single lens can accommodate every photographic requirement, and SLR cameras have always used removable lenses. A wide variety of lenses are available for each camera system, and many lenses that fit 35mm analog SLRs also fit digital SLRs. However, the CCD or CMOS sensor in a digital SLR is generally not as large as a 35mm film frame, and there is typically a multiplier factor in focal length. For example, using a multiplier factor of 1.5x, a 50mm lens on a 35mm camera is equivalent to a 75mm lens when attached to a digital SLR.

Through the Lens
In an SLR, the photographer sees the image through the actual picture lens. To compose the picture, a mirror reflects the light from the lens to the viewfinder. When the picture is taken, the mirror momentarily flips out of the way to allow the light to pass through the lens diaphragm to the CCD or CMOS sensor (or to film in an analog SLR). Through-the-lens viewing enables precise manual focusing because tiny LCD screens do not have sufficient resolution. In addition, holding the camera against the face helps steady it.

With most digital SLRs, the LCD screen is used to review the recorded image, not to preview it for picture taking. In 2006, Olympus introduced the first DSLR with an LCD preview. See digital camera and Four Thirds system.

Beware the Dust!
Unlike an analog SLR, which uses a completely fresh film frame for each photo, the digital SLR uses the same sensor chip for every image. Unfortunately, that sensor is susceptible to dust, which is why DSLR users are advised to keep a lens on the camera at all times. In 2007, DSLRs began to include some form of built-in dust reduction or removal.

Cleaning the Sensor
DSLRs have a "mirror lockup" function that flips the mirror out of the way to expose the sensor for cleaning, and there is a raft of sensor cleaning materials on the market that cost from a few dollars to several hundred. For a comprehensive overview of all cleaning methods, visit www.cleaningdigitalcameras.com.

Single Lens Reflex ( SLR) Cameras

Single-lens reflex camera

The single-lens reflex (SLR) camera uses an automatic moving mirror system which permits the photographer to see exactly what will be captured by the film or digital imaging system, as opposed to non-SLR cameras where the view through the viewfinder could be significantly different from what was captured on film.

Prior to the development of SLR, all cameras with viewfinders had two optical light paths: one path through the lens to the film, and another path positioned slightly off to the side seen by the photographer. Because the viewfinder and the film lens cannot share the same optical path, the viewfinder is aimed to intersect with the film lens at a fixed point somewhere in front of the camera. This is more or less helpful for pictures taken at a middle or longer distance but a close-up shot framed in the viewfinder will not look the same as the film image. Moreover, focusing the lens of a non-SLR camera when it is opened to wider apertures (such as in low light or while using low speed film) is not easy.

SLR cameras permit direct viewing using a pentaprism situated above the optical path through the lens to the film plane. Light is reflected by a movable mirror upwards into the pentaprism where it is reflected several times until it aligns with the viewfinder. When the shutter is released, the mirror moves out of the light path and the light shines directly onto the film, or in the case of a DSLR, the CCD or CMOS imaging sensor.

The focus can be adjusted manually by the photographer or automatically by the autofocus system. The viewfinder can include a matte focusing screen located just above the mirror system to diffuse the light. This system permits accurate viewing, composing and focusing, especially useful with interchangeable lenses.

Up until the 1990s, SLR was the most advanced photographic preview system available. But the recent development and refinement of digital imaging technology with an on-camera live LCD preview screen has overshadowed SLR's popularity. Nearly all inexpensive compact digital cameras now include an LCD preview screen allowing the photographer to see exactly what the CCD is capturing. However, SLR is still popular in high-end and professional cameras, because the pixel resolution, contrast ratio, and color gamut of an LCD preview screen cannot compete with the clarity and shadow detail of a direct-viewed optical SLR viewfinder.

Optical components of an SLR camera

Cross-section view of SLR system:
1 - Front-mount Lens (4 element Tessar design)
2 - Reflex Mirror at 45 degree angle
3 - Focal Plane Shutter
4 - 35 mm Film or Sensor
5 - Focusing Screen
6 - Condenser Lens
7 - Optical Glass Pentaprism (or Pentamirror)
8 - Eyepiece (can have diopter correction ability)

A cross-section (or 'side-view') of the optical components of a typical SLR camera shows how the light passes through the lens assembly (1), is reflected by the mirror (2) and is projected on the matte focusing screen (5). Via a condensing lens (6) and internal reflections in the roof pentaprism (7) the image appears in the eyepiece (8). When an image is taken, the mirror moves upwards from its critical 45 degree angle in the direction of the arrow, the focal plane shutter (3) opens, and the image is projected onto the film or sensor (4) in exactly the same manner as on the focusing screen.

This feature distinguishes SLRs from other cameras as, the photographer sees the image composed exactly as it will be captured on the film or sensor (see Advantages below).

Pentaprisms and penta-mirrors

Most SLRs use a roof pentaprism or penta-mirror to direct the light to the eyepiece, but there are other finder viewing capabilities, such as the waist-level finder, the interchangeable sports finders used on the Canon F1, F1n and new F1; the Nikon F, F2, F3, F4 and F5; and the Pentax LX

Another prism design was the porro prism system used in the Olympus Pen F, the Pen FT, the Pen FV half-frame 35 mm SLR cameras. This was later utilized on the digital Olympus EVOLT E-300 and E-330 DSLR cameras.

Lastly, a photographer can also purchase a right-angle finder which slips onto the eyepiece of most SLR's and D-SLR's and allows viewing sans a waist-level finder. There is also a finder which provides EVF remote capability.

Shutter mechanisms

Focal plane shutters

Almost all contemporary SLRs use a focal plane shutter located in front of the film plane, which prevents the light from reaching the film even if the lens is removed, except when the shutter is actually released during the exposure. There are various designs for focal plane shutters. Typical focal plane shutters designed in the fifties and continuing through part of the 1990's consisted of cloth material with two curtains: an opening shutter curtain followed by a closing shutter curtain. During fast shutter speeds, the focal plane shutter would form a 'slit' whereby the second shutter curtain was closely following the first opening shutter curtain to produce a narrow, vertical opening, with the shutter slit moving horizontally. The slit would get narrower as shutter speeds were increased.

Other focal plane shutter designs such as the Copal, travelled vertically. These were constructed of titanium foil and were metal-bladed (resembling something like a 'venetian blind'), and resulted in faster flash synchronization. Certain horizontally travelling focal plane shutters were also constructed of titanium foil as is the case with the Nikon F, F2, F3, F4, F5 and F6 35mm SLR cameras, and the Canon F-1 camera series. A unique focal plane shutter design was the rotary shutter used in the Olympus Pen half-frame 35 mm SLR camera system. This shutter system was also titanium foil but consisted of one piece of metal with a fixed opening, and this shutter system allowed electronic flash (EF) synchronization up to and including its top shutter speed of 1/500 of a second, thereby rivaling leaf-shutter EF capabilities.

Leaf shutters - Two Types

Another shutter system is the leaf shutter, whereby the shutter is constructed of diaphragm-like blades and can be situated either between the lens or behind the lens. If the shutter is part of a lens assembly some other mechanism is required to ensure that no light reaches the film between exposures. The leaf shutter can either be situated between the lens or behind the lens assembly.

An example of a behind-the-lens leaf shutter is found in the 35 mm SLR's produced by Kodak, with their Retina Reflex camera line; Topcon, with their Auto 100; and Kowa with their SE-R and SET-R reflexes.

A primary example of a medium-format SLR with a between-the-lens leaf shutter system would be Hasselblad, with their 500C, 500CM, 500 EL-M (a motorized Hasselblad) and other models (producing a 2 1/4" square negative {or 6 cm x 6cm metric}). Hasselblads use an auxiliary shutter blind situated behind the lens mount and the mirror system to prevent the fogging of film.

Other medium-format SLRs also using leaf shutters include the now discontinued Zenza-Bronica camera system lines such as the Bronica ETRs, the ETRs'i (both producing a 6 cm. x 4.5 cm. image), the SQ and the SQ-AI (producing a 2 1/4" or 6 x 6 cm. image like the Hasselblad), and the Zenza-Bronica G system (2 1/4" x 2 3/4" inch or 6 cm. x 7 cm.). Certain Mamiya medium-format SLRs, discontinued camera systems such as the Kowa 6 and a few other camera models also used between-the-lens leaf shutters in their lens systems.

Thus, anytime a photographer purchased a lens for the Hasselblad, with the exception of the older Hasselblad 1000f and other focal-plane shutter Hasselblads; or the Zenza-Bronica ETR, ETR-S, ETR-Si, the SQ, the SQ-Ai, the SQ-B, and the G series (with the exception of older Bronica cameras such as the Bronica Deluxe, the Bronica S, the Bronica S2), or the bigger system Mamiya RB-67, RB-67 Pro, RB-67 Pro S (mechanical) and RZ (electronically controlled shutter) cameras, that lens included a leaf shutter in its lens mount.

Because leaf shutters synchronized electronic flash at all shutter speeds especially at fast shutter speeds of 1/500 of a second or faster, cameras utilizing leaf shutters were more desired by studio photographers who used sophisticated studio electronic flash systems.

Some manufacturers of medium-format 2 1/4" SLR cameras also made leaf-shutter lenses for their focal plane shutter models. Rollei made at least two such lenses for their Rolleiflex SL-66 medium format, 2 1/4" camera, which was a focal-plane shutter SLR. Rollei later switched to a camera system of leaf-shutter design, (i.e., the 6006 and 6008 reflexes to name a few) and their current medium-format SLR's are now all of the between-the-lens shutter design.

Rotary shutter

One unusual design, the Olympus Pen half-frame 35 mm SLR system, manufactured by Olympus in Japan, used a rotary focal plane shutter mechanism which was extremely simple and elegant in design, and enabled the photographer to synchronize electronic flash at all shutter speeds, including the shutter's limit to 1/500 of a second. The camera started out meterless with the introduction of the Olympus Pen F; this camera required a two-stroke advance of the advance lever. The later models, the Olympus Pen FT and the Olympus Pen FV only required a single stroke of the film advance lever to position the film to the next frame. The Olympus Pen FT has a behind-the-lens metering system and was composed of a number of impressive optics from a 20 mm lens up to an 800 mm catadioptric (mirror) telephoto lens. The system included 'fast' lenses such as the 38mm f/1.8 Zuiko, the 40mm f/1.4 Zuiko and the 42mm f/1.2 Zuiko, all considered 'normal' lenses for this format. Olympus also made a 38mm f/3.5 macro lens, and a bellows extension attachment. There were also various lens adapters and other accessories for this camera.

As further, minor note on rotary shutters, only one other 35 mm camera system used a rotary shutter, and this camera system was the Robot Royal cameras, most of which were rangefinder 35 mm cameras. Some of these cameras were full-frame; some were half-frame, and at least one Robot camera produced an unusual square-sized image on the 35 mm frame.

Further developments

Since the technology became widespread in the 1970s, SLRs have become the main photographic instrument used by dedicated amateur photographers and professionals. Some photographers of static subjects (such as architecture, landscape, and some commercial subjects), however, prefer view cameras because of the capability to control perspective.^[1] With a triple-extension bellows 4" x 5" camera such as the Linhof SuperTechnika V, the photographer can correct certain distortions such as 'keystoning', where the image 'lines' converge (i.e., photographing a building by pointing a typical camera upward to include the top of the building). Perspective correction lenses are available in the 35 mm and medium formats to correct this distortion with film cameras, and it can also be corrected after the fact with photo software when using digital cameras. The photographer can also extend the bellows to its full length, tilt the front standard and perform photomacrography (commonly known as 'macro photography'), producing a sharp image with depth-of-field without stopping down the lens diaphgram.

History

Main article: History of the single-lens reflex camera

The (Pentax) Asahiflex	The 35 mm film-based Nikon F	Olympus The 35 mm film-based Olympus OM-2, which was the first SLR to measure light for electronic flash off of the shutter curtain.	Two Classic 35 mm SLR film cameras: the Canon AE-1 and the Minolta X-700
Nikon F5 professional SLR	Digital SLR Nikon D200 and a Nikon film scanner

Large format SLR cameras were probably first sold in 1884.^[2] The Ihagee Kine-Exakta was the first 35 mm SLR^{[citation needed]} and it was truly influential. Further Exakta models, all with waist-level finders, were produced up to and during World War II. Another ancestor of the modern SLR camera was the Swiss-made Alpa, which was innovative, and influenced the later Japanese cameras. The first eye-level LSR viewfinder was patented in Hungary on August 23, 1943 by Jenő Dulovits, who then designed the first 35 mm camera with one, the Duflex, which used a system of mirrors to provide a laterally correct, upright image in the eye-level viewfinder. The Duflex, which went into serial production in 1948, was also the world's first SLR with an instant-return (a.k.a. autoreturn) mirror.

The first commercially produced SLR that employed a roof pentaprism was the East German Contax S, announced on May 20, 1949.

The historic Contax S, the first pentaprism SLR for eye-level viewing

The Japanese adopted and further developed the SLR. In 1952, Asahi developed the Asahiflex and in 1954, the Asahiflex IIB. In 1957, the Asahi Pentax combined the fixed pentaprism and the right-hand thumb wind lever. Nikon, Canon and Yashica introduced their first SLRs in 1959 (the F, Canonflex, and Pentamatic, respectively).

Through-the-lens light metering (also known as "behind-the-lens metering")

As a small matter of history, the first 35 mm camera (non-SLR) to feature through the lens light metering may have been Nikon, with a prototype rangefinder camera, the SPX. According to the below website, the camera used Nikon 'S' type rangefinder lenses (See website: http://www.cameraquest.com/nrfstory.htm).

In the SLR design scheme, there were various placements made for the metering cells, all of which utilized CdS (Cadmium sulfide) photocells. The cells were either located in the pentaprism housing, where they metered light transmitted through the focusing screen; underneath the reflex mirror glass itself, which was Topcon's design; or in front of the shutter mechanism, which was the design used by Canon with their Canon Pellix.

Pentax was the first manufacturer to produce and show the first working prototype 35 mm behind-the-lens metering SLR camera, which they named the Pentax Spotmatic. The camera was first shown at a Photokina show circa 1960-1961. Later, Through-the-lens (TTL) light metering SLRs were introduced to the photographic market in the early 1960s, starting with the 1963 production model Topcon RE Super which metered the light directly from a CdS metering system etched under the mirror/glass assembly. This system metered the light using an average metering system. Approximately one year later, in 1964, a production model of the Pentax Spotmatic was shown whose CdS light meter cells were housed in the pentaprism housing, reading the light coming upwards through the focusing screen. Pentax had reverted their original spot-metering design to an average metering scheme.

Mamiya Sekor came out with cameras such as the Mamiya Sekor TL and various other versions. Yashica introduced the TL Super. Both of these cameras used M42 screw thread lenses as did the Pentax Spotmatic. Later on Fujica introduced their ST-701, then ST-801 and ST-901 cameras. The ST-701 was the first SLR to use a silicon cell photodiode, which was more sensitive than CdS and was immune to the memory effect that the CdS cell suffered from in bright sunlight. Gradually, other 35 mm SLR camera manufacturers changed their behind-the-lens meters from CdS cells to Silicon Diode photocells.

Other manufacturers responded and introduced their own behind-the-lens metering cameras. Nikon and Miranda, at first, simply upgraded their interchangeable pentaprisms to include behind-the-lens metering (for Nikon F, and Miranda D, F, Fv and G models) and these manufacturers also bought out other camera models with built-in behind-the-lens metering capability, such as the Nikkormat FT and the Miranda Sensorex (which used an external coupling diaphragm). Minolta introduced the SRT-101, which used Minolta's proprietary system which they referred to as "CLC", which was an acronym for "contrast light compensation", which metered differently from an average metering behind-the-lens camera.

Some German manufacturers also introduced cameras such as the Zeiss Ikon Contarex SE, which was the only 35 mm SLR to use interchangeable film backs.

Inexpensive leaf-shutter cameras also benefited from behind-the-lens metering as, Topcon introduced the Auto 100 with front-mount interchangeable lenses designed only for that camera, and one of the Zeiss Ikon Contaflex leaf shutter cameras. Kowa manufactured their SET-R which had similar specifications.

Within months, manufacturers decided to bring out models that provided limited area metering, such as Nikon's Photomic Tn finder, which concentrated 60% of the CdS cells sensitivity on the inner circle of the focusing screen and 30% on the surrounding area. Canon used spot metering in the unusual Canon Pellix camera, which also had a stationary mirror system that allowed approximately 70% of the light to travel to the film plane and 30% to the photographer's eye. This system, unfortunately, degraded the native resolution of the attached lens and provided less illumination to the eyepiece. It did have the advantage of having less vibration than other SLR cameras but this was not sufficient to attract professionals to the camera in numbers.

Semi-automatic exposure capabilities

While auto-exposure was commonly used in the early 1960s with various 35 mm fixed lens rangefinder cameras such as the Konica Auto 'S', and other cameras such as the Polaroid Land cameras whose early models used selenium cell meters, auto-exposure for interchangeable lens SLR's was a feature that was largely absent, except for a few early leaf-shutter SLR's such as the Kowa SE-R and Topcon Auto 100.

The types of automation found in some of these cameras consisted of the simple programmed shutter, whereby the camera's metering system would select a mechanically-set series of apertures with shutter speeds, one setting of which would be sufficient for the correct exposure. In the case of the above-mentioned Kowa and Topcon, automation was semi-automatic, where the camera's CDs meter would select the correct aperture only.

Autoexposure, technically known as semi-automatic exposure, where the camera's metering system chooses either the shutter speed or the aperture, was finally introduced by the Savoyflex and popularized by Konishiroku in the 1965 Konica Auto-Reflex. This camera was of the 'shutter-priority' type automation, which meant that the camera selected the correct aperture automatically. This model also had the interesting ability to photograph in 35 mm full-frames or half-frames, all selected by a lever.

Other SLR's soon followed, but because of limitations with their lens mounts, the manufacturers of these cameras had to choose 'aperture-priority' automation, where the camera's metering system selects the correct shutter speed. As one example, Pentax introduced the Electro Spotmatic, which was able to use the then considerable bulk of 42 mm screw-mount lenses produced by various manufacturers. Yashica, another screw-mount camera manufacturer, soon followed.

Canon, which produced the FD lens mount (known as the breech-mount; a unique lens mounting system that combines the advantages of screw-mount and bayonet-mount) introduced their shutter priority 35 mm SLR, the Canon EF in 1976 or so. This camera's build quality was almost the equal of their flagship camera, the Canon F1, and featured a copal-square vertically-travelling focal plane shutter which could synchronize electronic flash at shutter speeds up to and including 1/125 of a second, thus making this a good second-body camera for the professional photographer.

Nikon at first, produced an aperture-priority camera, but later made subtle changes on the inside of their bayonet mount and soon, shutter-priority automation was achieved.

Full Program Auto-Exposure

Minolta XD-11 (also XD-7 and XD)
Type	35 mm SLR
Lens mount	Minolta MD mount
Focus	Manual focus SLR
Exposure	Shutter and Aperture priority autoexposure
Flash	Hot shoe only; no PC connector
Dimensions	51 x 86 x 136 mm, 560 g

Full-program auto-exposure soon followed with the advent of the Minolta XD-11.^[3] This SLR had a 'P' mode on the shutter speed dial, and a lock on the aperture ring to allow the lens to be put on 'Auto' mode. Other manufacturers soon followed with Nikon introducing the FA, Canon introducing the A1, and Pentax introducing the Super Program. Olympus, however, continued with 'aperture-priority' automation in their OM system line.

The 1970s and 1980s saw steadily increasing use of electronics, automation, and miniaturization, including integrated motor driven film advance with the Konica FS-1 in 1979, and motor rewind functions.

Autofocus

The first phase detection SLR TTL autofocus 35 mm SLR was 1981's Pentax ME-F.^[4] The Minolta Maxxum 7000, released in 1985, was the first 35 mm SLR with integrated motorized autofocus and film-advance winder, which became the standard configuration for SLR cameras from then on. This development had significant impact on the photographic industry.

Some manufacturers discarded their existing lens systems to compete with other manufacturer's autofocus capability in their new cameras. This was the case for Canon, with its new EOS lens line. Other manufacturers chose to adapt their existing lens systems for autofocus capability, as was the case with Nikon and Pentax. Still some manufacturers, notably Leica with its R-system lenses, and Contax with its Zeiss lenses, decided to keep their lens mounts non-autofocus. Before the Contax camera and lens line was totally discontinued, Contax did come out with autofocus and digital camera capability, evidenced in the Contax N-Digital. Unfortunately this model was too late and too expensive for competition with other camera manufacturers. The Contax N-digital was the last Contax to use that maker's lens system, and the camera, while having impressive features such as a full-frame sensor, lacked sufficient write-speed to the memory card for it to be seriously considered by some professional photographers.

From the late 1980s competition and technical innovations made 35 mm camera systems more versatile and sophisticated by adding more advanced light metering capabilities such as spot-metering; limited area metering such as used by Canon with the F1 series; matrix metering as used by Nikon, exposure communication with dedicated electronic flash units. The user interface also changed on many cameras, replacing meter needle displays which were galvanometer-based and thereby fragile, with light-emitting diodes (LEDs) and then with more comprehensive liquid crystal displays (LCDs) both in the SLR viewfinder and externally on the cameras' top plate using an LCD screen. Wheels and buttons replaced the shutter dial on the camera and the aperture ring on the lens on many models, although some photographers still prefer shutter dials and aperture rings. Some manufacturers introduced image stabilization on certain lenses to combat camera shake and to allow longer hand-held exposures without using a tripod. This feature is especially useful with long telephoto lenses.

Digital SLRs (DSLRs)

Main article: Digital single-lens reflex camera

Canon, Nikon and Pentax have all developed digital SLR cameras using the same lens mounts as on their respective film SLR cameras. Konica Minolta did the same, but in 2006 sold their camera technology to Sony, who now build DSLRs based on the Minolta lens mount. Samsung builds DSLRs based on the Pentax lens mount. Olympus, on the other hand, chose to create a new digital-only Four Thirds System SLR standard, adopted later by Panasonic and Leica.

Film formats

Early SLRs were built for large format photography, but this film format has largely lost favor among professional photographers. SLR film-based cameras have been produced for most film formats as well as for digital formats. These film-based SLRs use the 35 mm format as, this film format offers a variety of emulsions and film sensitivity speeds, usable image quality and a good market cost. 35 mm film comes in a variety of exposure lengths: 20 exposure, 24 exposure and 36 exposure rolls. Medium format SLRs provide a higher-quality image with a negative that can be more easily retouched than the smaller 35 mm negative, when this capability is required.

A small number of SLRs were built for APS such as the Canon IXUS and the Nikon Pronea cameras. SLRs were also introduced for film formats as small as Kodak's 110, such as the Pentax Auto 110 which had interchangeable lenses.

Common features

Other features found on many SLR cameras include through-the-lens (TTL) metering and sophisticated flash control referred to as 'dedicated electronic flash'. In a dedicated system, once the dedicated electronic flash is inserted into the camera's hot shoe and turned on, there is then communication between camera and flash. The camera's synchronization speed is set, along with the aperture. Many camera models on the market today actually measure the light that reflects off of the film plane, controls the flash duration of the electronic flash (some flash units have a flash duration range of 1/1000 of a second to 1/50,000 of a second), and then terminate exposure when the camera has received enough light for the exposure.

Some electronic flash units can send out several short bursts of flash to measure the distance, use the camera's inboard sensor(s) to determine the amount of light that is reflected from the subject, then send out a main pulse of light of just the right amount of light energy for a perfectly exposed photograph. Sophisticated cameras can even make it easy for the photographer to balance electronic flash and available light for an evenly balanced scene. While these capabilities are hardly unique to the SLR, manufacturers included them early on in the top models, whereas the best rangefinder cameras adopted such features later.

Cut-away of a Minolta XG7 film-based SLR

Advantages

Many of the advantages of SLR cameras derive from viewing and focusing the image through the attached lens. Most other types of cameras do not have this function; subjects are seen through a viewfinder that is near the lens, making the photographer's view different from that of the lens. SLR cameras provide photographers with precision and confidence; they provide a viewing image that will be exposed onto the negative exactly as it is seen through the lens. There is no parallax error, and exact focus can be confirmed by eye — especially in macro photography and when photographing using long telephoto lenses. The depth of field may be seen by stopping down to the attached lens aperture, which is only possible on most SLR cameras except for the least expensive models. Because of the SLR's versatility, most manufacturers have a vast range of lenses and accessories available for them.

Compared to most fixed-lens compact cameras, the most commonly used and inexpensive SLR lenses offer a wider aperture range and larger maximum aperture (typically f/1.4 to f/1.8 for a 50 mm lens). This allows photographs to be taken in lower light conditions without flash, and allows a narrower depth of field, which is useful for blurring the background behind the subject, making the subject more prominent. 'Fast' lenses are commonly used in theater photography, portrait photography, surveillance photography, and all other photography requiring a large maximum aperture.

The variety of lenses also allows for the camera to be used and adapted in many different situations. This provides the photographer with considerably more control (i.e., how the image is viewed and framed) than would be the case with a view camera. In addition, some SLR lenses are manufactured with extremely long focal lengths, allowing a photographer to be a considerable distance away from the subject and yet still expose a sharp, focused image. This is particularly useful if the subject includes dangerous animals (e.g., wildlife); the subject prefers anonymity to being photographed; or else, the photographer's presence is unwanted (e.g., celebrity photography or surveillance photography). Practically all SLR and DSLR camera bodies can also be attached to telescopes and microscopes via an adapter tube to further enhance their imaging capabilities.

Disadvantages

In most cases, single-lens reflex cameras cannot be made as small or as light as other camera designs — such as rangefinder cameras, autofocus compact cameras and digital cameras with electronic viewfinders (EVF) — owing to the mirror box and pentaprism/pentamirror. The mirror box also prevents lenses from having rear elements closer to the film or sensor to be mounted unless the camera has a mirror lockup feature; this means that simple designs for wide angle lenses cannot be used. Instead, larger and more complex retrofocus designs are required.

During an exposure the viewfinder is blocked

The SLR mirror 'blacks-out' the viewfinder image during the exposure. In addition, the movement of the reflex mirror takes time, limiting the maximum shooting speed. The mirror system can also cause noise and vibration. Partially-reflective (pellicle) fixed mirrors avoid these problems and have been used in a very few designs including the Canon Pellix and the Canon EOS-1N RS, but these designs introduce their own problems. These pellicle mirrors reduce the amount of light travelling to the film plane or sensor and also can distort the light passing through them, resulting in a less-sharp image. To avoid the noise and vibration, many professional cameras offer a mirror lock-up feature, however, this feature totally disables the SLR's focusing ability.

Currently, most digital SLRs cannot display a live preview on their rear LCD displays, unlike digicams or bridge cameras, and must be held to the eye to view and compose the image. This situation is changing with the arrival of the Olympus E-330, Olympus E-410, Olympus E-510, Panasonic DMC-L1, Panasonic DMC-L10, Leica Digilux 3, Canon EOS 40D, Canon EOS 450D, Canon EOS-1D Mark III, and Nikon D300 cameras.

Electronic viewfinders have the potential to give the 'viewing-experience' of a DSLR (through-the-lens viewing) without many of the disadvantages, but as of 2006 sensor capability and display technology is insufficient for wide acceptance among the advanced amateur or professional markets that purchase and use digital SLRs. The SLRs and DSLRs will probably continue as the foremost system because of the superiority in the use of the viewing and focusing optical system.

Movie Modes

Movie modes are not available on current DSLRs, as the current focus has been to optimize these cameras to provide the best possible quality and convenience in taking 'still' images. This situation may change in the future with more technological advancements.^[5]

Reliability of SLRs

SLRs vary widely in their construction and typically have bodies made of plastic or magnesium. Most manufacturers don't cite durability specifications, but some report shutter life expectancies for professional models. For instance, the Canon EOS 1Ds MkII is rated for 200,000 shutter cycles and the newer Nikon D3 is rated for 300,000 with its exotic carbon fiber/kevlar shutter. Because many SLRs have interchangeable lenses, there is a tendency for dust, sand and dirt to get into the main body of the camera through the mirror box when the lens is removed, thus dirtying or even jamming the mirror movement mechanism or the shutter curtain mechanism itself. In addition, these particles can also jam or otherwise hinder the focusing feature of a lens if they enter into the focusing helicoid. The problem of sensor cleaning has been somewhat reduced in DSLRs as some cameras have a built-in sensor cleaning unit.

Price and Affordability

The price of SLRs in general also tends to be somewhat higher than that of other types of cameras, owing to their internal complexity. This is compounded by the expense of additional components, such as flashes or lenses. The initial investment in equipment can be prohibitive enough to keep some casual photographers away from SLRs, although the market for used SLRs has become larger particularly as photographers migrate to digital systems.

The future of SLRs

For the foreseeable future, film-based SLRs may still be produced, as is still the case with the 35 mm film-based Nikon F6, and some other 35 mm SLR models. This may also be true with some medium-format film-based SLRs. It appears inevitable that the Digital Single Lens Reflex camera design will eclipse film SLR's design in convenience, sales and popularity. These cameras are currently the marketing 'favorite' among advanced amateur and professional photographers. Only those photographers who need a film-based SLR will continue to buy and use such an instrument.^{[6] [7] [8]}