I should have learned fairly early in my photographic life that camera bodies were not the reliable, infallible devices I imagined them to be (and that far too many photographers still imagine them to be). Back when I was in college, I remember the early reviews of the Pentax 6x7 commenting that the relatively straight film path in that camera did a much better job of holding the film flat than the serpentine path in cameras that used film magazines, like Hasselblads and Rolleis.
In truth, that's the only time I can recall a mass circulation magazine suggesting that this might even be an issue. Clearly insiders were aware that some things might be rotten in Denmark, but the news rarely made it to us consumers. When I talked about "pernicious secrets" in my last column, I was thinking of incidents like that. The big lie by omission; reviews rarely talked about how badly camera bodies performed, so one simply didn't think about the fact that they performed badly. So, I read it, noted it, and then managed to forget it.
In the late 1970s I bought a Canonet GIII QL 17. That was a relatively inexpensive and compact rangefinder that came equipped with a remarkably good ƒ/1.7 lens. It was a little soft wide open (would have rated a "very good" by the lens tests of the time), but once you got it down to ƒ/4.5 or ƒ/5.6, it was brilliant. I mean that both figuratively and visually. I was very happy with it.
Several years later I read an article that talked about the desirability of having one's rangefinder cameras periodically checked for focus accuracy. It was a notion that hadn't occurred to me before. I ran some tests on my toy and, big surprise, the focus wasn't anywhere close to being accurate. Being a brave soul I took off the top of the camera, dug into the rangefinder mechanism, and found the two set screws that adjusted the focus. Through a process of considerable trial and error, I managed to get the camera into some semblance of decent focus. I even got reassembled correctly. Usually that doesn't happen; I'm better at deconstruction.
(Please do not post comments nor send me e-mails requesting any sort of assistance on disassembling or adjusting your camera. If you can't figure out how to do it yourself, I'm not going to help you break it.)
Miraculously, that ƒ/1.7 lens became achingly sharp even wide open.
When I bought a Pentax ME Super with 50 mm ƒ/1.7 lens in 1983, the first thing I did was run some lens tests. Because, of course, the lens is what really counts. Right? I still hadn't entirely internalized the lessons from the Canonet. Stopped down, that lens would put in excess of 100 line pairs per millimeter on film without breaking a sweat (I learned later that I had lucked into buying one of the better 50mm lenses that's ever been made). Wide open, though, I was seeing a so-so-by-my-standards 60 line pairs per millimeter (the magazine test standards of the time would have given this lens a near-excellent rating).
Pentax ME Super with 50mm ƒ/1.7 lens. Photo from here.
Now I remembered that important lesson. I ran a focus test on my Pentax, and sure enough it was decent, within manufacturing tolerances, but it was not spot on. I tweaked it until it was, and I reran my lens tests. Wide open, that lens would put over 100 line pair per millimeter on film. At ƒ/4.8 I could hit 150 line pairs per millimeter.
After that, I never bought a camera nor tested one for review where I didn't give the body a very thorough going over. Rarely, if ever, did I find one that was in the best possible adjustment. That held true for a quarter-century. I'd be most surprised if it's changed today.
Of course, some things aren't fixable. Aerial tests on medium format lenses show that the best of them can peak at over 200 line pair per millimeter. I rarely, if ever saw more than 70 line pair per millimeter in 6x6 or 6x7 format; the cameras simply didn't control the film plane well enough. My Fujica GA 645 could hit 100 line pair per millimeter...were it not for the fact that the autofocus mechanism wasn't anywhere near that accurate.
Which takes me to my last point: I've just been talking about one aspect of camera performance: accuracy of manual focus. I haven't told you about the myriad ways that autofocus does go wrong, or the rather substantial problems with getting accurate and repeatable exposure out of a camera body, or the ways in which the camera body and the lens don't interface quite like they're supposed to (a shared problem). Oh, I could write so many more columns. I will spare you, if you promise to take the underlying revelation to heart sans elaborate exposition.
P.S. I'm off to Montréal for 10 days, so if responses to comments are few and far between, that'll be the reason why.Ctein's weekly column appears on TOP every Thursday morning.
Send this post to a friend
Note: Links in this post may be to our affiliates; sales through affiliate links may benefit this site. More...
Original contents copyright 2010 by Michael C. Johnston and/or the bylined author. All Rights Reserved.