On Autofocus In Still Cameras (A Rant!)

OK, here comes the rant! (You were warned! ;-)

AF is, in my 'umble opinion, one of the silliest things foisted on us by mfgrs. seeking to sell whole new sets of gear to consumers...!

-- AF doesn't work well (if you have a good VF and proper eye-correction to see it well, the common AF errors are all too obvious).
-- AF is harder to use (the "focused" area must be in the center, then the focus locked for reframing [often too slow a process for action work] - and AF is slower than a good MF optical system for anyone used to MF).
-- To make people feel they need AF (for what other reason?), most AF cameras have finders that are not sharp enough for good or easy MF.
-- Most lenses sold now are slow zooms, which are less practical for easy MF (I prefer non-zooms, which not only provide about 8 times the amount of light at the first good f-stop, but they are FAR easier to focus manually - these I find more "convenient" than slow, relatively poor zooms regardless of the width of the
FL range covered...).

While shooting an outdoor wedding reception, I decided to take three AF lenses (along with several MF lenses) to give AF another try. Using an AF body with a sharp finder (Nikon 8008 - no longer made, of course, since the VF is so good for MF...;-), it was necessary to switch off AF almost immediately in every situation I tried it in. With running and playing kids, the AF couldn't begin to keep up and MF with a 24mm f2.8 AF (and 16mm f3.5 MF) was reliable and easy. With groups
of people talking, the 28-70 was unacceptably cumbersome in AF and I missed many good "moments" with it until I went to MF - the 85mm f2 MF and 24mm AF used with manual focus were far easier to use at that point. Even with the slower zoom, I was faster and more accurate focusing with MF than when using the AF system. With totally static situations, the AF focus failure rate was still sufficiently high to induce a quick switch to MF. Before anyone says something like "Well, did you use the latest/best AF system?", I will say that I did not - but having followed and tried AF gear from the beginning to the present, I will say that with each "Well NOW they've got it right!" generation of AF cameras, I have seen little or no REAL improvement in AF, just claims... AF just doesn't work very well, in my experience (later, the F100 and F5 changed my mind on this...). For those who say, "My eyesight is too poor for MF", I recommend considering trying a glasses solution (described elsewhere in this section, at this link: Four-Distance Glasses). If you can see sharply around the one meter distance (the effective viewing distance of most SLR focusing screens), if you have a camera with a sharp viewfinder, and if you use MF lenses of about f2-2.8 max aperture, MF is so much easier and faster to use than AF, it is just plain silly to think about using AF! Even with long and fast teles with animals, the MF systems "pop" into focus anywhere in the frame - but lose AF center coverage for a moment and the long AF lenses search for focus, generally causing the photo opportunity to be lost. This same affect applies also to macro work with AF - I find it impractical. I find general photography impractical with AF also... For those who want "point and shoot" capability (and quality...), I recommend a good P&S camera - and they are generally much smaller than a P&S SLR + lens + flash rig... A good MF SLR system with a few top-class non-zooms (a good tele zoom can be a good addition, though, since tele zooms are usually better optically, easier to focus, and more useful than shorter zooms - and "foot-zooming" is less effective with long lenses than with short) is a practical rig, and more "convenient" than "do-all" wide-range AF zooms that are noticeably slower, harder to focus, and less sharp than a good MF rig. BTW, with a good viewing optical system (including good eye correction for one meter, a sharp camera viewfinder, and moderately fast non-zoom lenses), viewing screen "focus aids" occupying valuable territory in the center of the screen just get in the way of easy focus on a simple plain-matte ground-glass viewfinder screen...

(Part Two of the rant consists of extolling the advantages of center-weighted manual metering vs. the multi-segment program-exposure nonsense also foisted on us as necessary or desirable by the camera makers - but that is for another time...;-)

On Autofocus in Still Cameras, a Retraction...;-)

Since writing the above, an eye problem more difficult to deal with than the one so nicely solved by the glasses described in Four-Distance Glasses has left me looking again at autofocus. Fortunately, the Nikon F100 and F5 appear to have solved many of the problems described above, and I have added two F100s and several of those loose, icky-plastic AF lenses to my collection. Results have proven satisfactory, and with the successful use of the best AF gear, I now retract most of my anti-AF rant...;-)

[With many improvements in camera bodies having been made since the above was written, I can now cheerfully retract most of the above...;-]

"Hope This Helps"
David Ruether (d_ruether@hotmail.com)

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