“In general, I do not find the normal lens especially desirable functionally or aesthetically. In my experience, lenses of shorter or longer focal length are usually preferable in an aesthetic sense.”

— Ansel Adams, The Camera

As I may have mentioned, I’m a big supporter of the DX format. Like the Olympus PEN half-frame format of the sixties, it’s a new take on an old standard. Although the flange focal distance is the same, the smaller image circle and shorter focal length requirements of the APS-C sensor size result in smaller, lighter, less expensive lenses akin to the rangefinder.

The 35mm focal length has long be a favorite for it’s dynamic perspective and enhanced depth of field, especially amongst photojournalists. This focal length is now considered the “normal” focal length for the DX APS-C format. This may lead the casual photographer to believe that by shooting with this “normal” focal length, they are actually shooting wider, in support of Adam Ansel’s theory.

Unfortunately, they would be wrong.

The fact that the image is being cropped by the smaller sensor changes nothing in terms of the lens’s perspective. What does however, is how close the camera is to the subject. When you use a 35mm lens, your field of view widens, and you need to move in closer to achieve the equivalent crop of your subject. In the process of doing this the perspective changes, making elements in the background appear smaller. The good news is that your old 50mm “normal” lens really does become a 75mm portrait lens, and by continuing to use it, you are supporting Ansel’s theory.

The Case for FX
All of this is also the reason that FX/Full-frame will continue to be the format of choice amongst seasoned professionals. DX will never replace the FX format, but it does augment it. DX is simply the equivalent of shooting full-frame and cropping the image borders evenly at 66.66% directly in the camera for every photo we take. We just have the luxury of a viewfinder that accurately displays it. But, we may not always want this crop, and so the FX format will continue to give us the true focal length of our legacy lenses as they were originally intended.

More good news is, these differences in focal length become less pronounced as they become longer. So, if you’ve plunked down some good coin for that fast 85mm portrait lens, take heart; it’ll still work just fine, you’ll just have to step back about three and a half feet.

The price for an FX digital SLR is still pretty high. But until the next (and hopefully less expensive) generation becomes available, you can still shoot full-frame quite inexpensively. It’s called using film, and great film bodies are still going for next to nothing on the second market.