The distance scale has long been a useful tool for photographers since it provides a good deal of information about depth of field and focusing quickly and easily. Though it could be argued that autofocus has diminished the need for a distance scale it continues to grace most mid- and higher-end lenses, though in its current form I have no idea why.

The manual focus distance scale is a thing of beauty. It conveys a ton of information about the state of focus and depth of field on the lens.

For example, from the distance scale shown one can immediately see that this lens is focused at approximately 12 feet. One can quickly estimate the depth of field at any full stop aperture. Finally, if one were to shoot at f/22, this lens would be focused at the hyperfocal distance maximizing depth of field. Oh yes, and the red dot near the center mark, that’s the IR focus point.

That’s quite a lot of info that can be gleaned from some simple markings on a lens.

Now look at the modern distance scale. Gone is the ability to estimate depth of field, gone is the ability to easily focus at the hyperfocal point. All you can readily tell is that the lens is focused at about 10 feet.

The distance scales on autofocus lenses have clearly been gimped. Why?

Decreased need is certainly a major factor, though I’d argue that in its current state the autofocus distance scale is virtually useless. In fact I’d go so far as to suggest that the lens makers should save the few dollars it costs to put the currently useless distance scales on lenses and remove them completely.

The real tragedy is that both hyperfocal focusing and estimating depth of field aren’t useless even with autofocus cameras. Yet the ability to easily do those things easily has been removed and no functionality has replaced them. Considering the advanced nature of current cameras, it should be easy to focus the camera at the hyperfocal point at the push of a button, or display on one of the many LCDs (my vote goes for the shutter/aperture /ISO spot in the viewfinder when pressing the DoF preview button) the depth of field in some user configurable units. It’s just software, yet it’s not been done.

Needless, to say I don’t find modern distance scales very useful. If you use the distance scales on modern autofocus lenses regularly, leave a comment, I’d love to know.