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Why film is better and how digital cameras can be. by CedgeS · 2004-01-13 14:27 · Score: 2, Informative · on Kodak To Stop Selling Film Cameras In U.S.

Why film beats digital

Regular 35mm film has an optical resolution and information depth similar to about a 25 MegaPixel digital camera [1].

A more important measure of film or CCD quality are light collecting power. In photogrpahs light == information. More light collecting power leads to higher resolutions, greater depth of focus, and increased shutter speeds.

Light collecting power allows photographs to be taken at a faster speed through the same lens. To collect the most light possible into a camera, and thus the most information, we usually set the shutter speed to the slowest speed we can without blurring the scene - this is usually 1/90th of a second (Some photoraphers can hold a camera still for 1/45th of a second, normally tripods can do about 1/10th of a second). Then we adjust the other parameters of the camera to match this maximum-information shutter speed. To use up extra light and convert it into information we can increase the depth of focus of the camera (making the hole the light goes through smaller). The more light collecting power the film has, the greater depth of focus the camera can have.

Light collecting power also affects the maximum resolution of film or CCDs. For examle a slide film at ISO25 can capture about 4 times the information of a film at ISO100. The ISO25 film trades light collecting power for more pixels, which can function because there is enough light to expose them. ISO100 film can take pictures faster, because there are fewer picture elements that need the light collecting power, so more of it can be used to increase depth of focus and increase shutter speed for less blurred photographs. ISO800 or 1600 films expose very easily, but are greatly lacking in the resolution of the final image.

So, more light collecting power leads to more ability to collect information, depth of focus, and shutter speed.

How digital can beat film:

Digital cameras have some unique potential which will allow them to beat 35mm film in the near future. Medium and large-ormat digital cameras could potentially rival medium and large format film eventually. One of the potential ways to greatly increase the power of digital cameras is to increase their light collecting ability. Many scenes are relitivly motionless down to about 1/10th of a second, however our hands are not steady enough to photograph them easily. It would be a relatively simple task (simpler than correlating stereoscopic views) for a digital camera to repeatedly sample a CCD durring a long 1/10th sec. shot and remove the blurring and add the sampled frames together. This would greatly increase the light collecting power of the digital camera over film cameras in many regular types of shots, greatly increasing its information collecting ability. This increase in information collecting ability could be traded for increased resolution (if we are near the limit of having enough light to expose CCD elements), increased depth of focus, or increased shutter rates (limited by the fastest possible sampling rate of the CCD).

Re:Prints by Racine · 2003-12-13 02:03 · Score: 1 · on Would Ansel Adams Have Gone Digital?

I get my information from a) the saturated, data-less highlights I tend to see in many digital images, be they on a Canon A70 or a Nikon D100 (for ghastly examples of the latter look at the sample images on dpreview).

b) Ken Rockwell, a professional filmographer who shoots digital video for a living:

I quote from Kenrockwell.com

"Highlight Rendition: Digital still has a huge problem with highlight reproduction, presuming you, like me, shoot into the sun or other sources of light. Film for hundreds of years has naturally had "shoulders" in its characteristic curve. This means that even with severe overexposure in places that the highlights are rendered naturally on film, even contrasty slide film like the Velvia I love.

"On the other hand, at the dawn of the 21st century digital capture is more linear than log as film is. This means that digital cameras often have better shadow detail than my Velvia, but can have horrid, unnatural highlights if overexposed even a third of a stop.

"Specifically, digital clips hard as soon as you are a few stops over zone V. This could be OK, however unfortunately in color one of the three color channels (red, green or blue) usually clips first, throwing the hue (color) into all sorts of weird shifts in the areas the image transitions from bright to pure white. This is why digital camera images may show all sorts of nasty, unnatural hue (color) shifts in the brightest areas.

"Unfortunately this highlight issue is a basic characteristic of CCD sensors, amplifiers and sampling and quantization electronics and won't be fixed soon. To simulate film's shoulder one needs to add several more stops of highlight capture in the digital camera so the image processing electronics can use this information to simulate a decent shoulder curve. CCDs and the related capture electronics will need about ten times more dynamic range (three stops) than they have today to be able to simulate film's shoulder. Of course negative film has more range still, but that's not really relevant to good photography since the dynamic range of negative film already exceeds what you ought to be photographing. For instance, a negative can be way overexposed and still retain detail in otherwise blown out highlights, if you custom print and burn in those areas. Heck, you can scan a negative from a $6 disposable camera and have more highlight dynamic range than any digital capture system.

"The $100,000 three-CCD studio high-definition television cameras around which I work today still have problems with this, and so our cheap $5,000 single-striped CCD digital SLRs will, too. Everyone is working on solving this. This is the biggest image defect in digital cameras today."

General Comments, Camera Hints by Whatsmynickname · 2003-12-09 17:02 · Score: 2, Insightful · on Best 35mm SLR Camera for Beginners?

The first thing you should do is sit down and ask yourself "what kind of photography are you going to do"? Family outings, travel, scenery, sports, ??? Then pick the best (beginners) camera / lens for the job. For example, sports or photojournalism photographers lean towards a 35mm / digital SLR with a telephoto or zoom lens. Same with bird / animal nature photography. OTOH, scenery photographers tend to either lean towards 35mm with low grain film or medium format cameras. When I take pictures on a family outing, I want to travel light as possible (ie, don't want any clunky 35mm when an ultralight digital point and shoot (P&S) will do). So the first question is "what do you want to shoot"?

IMHO, based on the type of shots you want, choose the lens(es) [brand name and focal length], and that will dictate what body you will get. Try to get a quality lens. Once you buy the camera, it doesn't make sense to have to immediately resell the camera body AND lens when you want to expand and find out your options are limited, so think of it as buying into a family.

IMHO, you may want manual control when learning, but you will eventually want some automation down the road. This is especially when newer camera automated metering systems (such as Nikon's N65 or N75) do so well nowadays. Whatever you do, go to a camera store and check out the "user interface" to see how easy it is to do something in manual mode...

Here's a site that I believe has good advice on cameras in general and all the newest cameras. Don't forget to check out his gallery as well!

Film is another important choice. IN GENERAL, higher film "speeds" allow more opportunities to shoot, but lower film speeds tend (I say TEND) to have finer grain (read sharper) pictures. High speed film has gotten much better nowadays, grain wise. Slide film has more vivid colors, but is more contrasty, so it's harder to shoot in areas with bright/shadowy areas. Print (negative) film has more "latitude" or less contrasty, but generally doesn't have the visual impact of slides. Portrait photograpy tends to use print film, nature or scenery tends to use slides. Digital tends to be vivid like slide film, depending upon the camera / sensor, but it's "latitude" is generally less than film (here come the flames!).

I know I'm gonna get flamed for this, but I totally disagree that film is better to learn photography on than digital. You would be right in saying a film SLR is better than a digital point and shoot, but a digital SLR (Canon 300D) would allow you to see what shutter speed and lens aperture does for the shot just as well as any film. Plus, you don't have to wait day(s) to see what the results of your settings are. I only caution you to check out the user interface of the digital SLR to see how easy it is to shoot totally manual.

What did I do? I started with a Nikon FM with 24mm and 20mm lens for scenery photography a long time ago. I use a Nikon CP700 for family outings. I recently bought a used Mamiya 1000s system for $400 at KEH for scenery photography (totally MANUAL). I use Fuji's Velvia 50 slide and I also bought a Epson 3170 scanner to digitize the photos. It's been trial and error, but I love the eye popping color and resolution when I get it right! I can also get my pics drum scanned and professionally printed if I choose, so I like my setup...