If you try holding the focus button down on other Canon 1 series models you get the same focusing noise in AI servo when focused on a stationary target. It is easier to hear on a non-USM lens. I tried it on a 1DMK3 with a Tamron 28-75 which has a noisier focus motor. I think it is the way the 1 series AF (at least in the 3 and 4) works. Forget about and go make some great images!
, obviously the sky isn't falling ... and I didn't imply that it was.
Look, it should be obvious to everybody that all (both new and old) lenses are primarily a mechanical device and continuously wear out. If a new camera is designed, optimized, and tested by Canon's engineering staff using only factory calibrated perfect lenses and for some reason chattering and/or oscillations occur when using a few (not all) older lenses then Canon would not be aware of the issue and the Geritol lens population will subsequently wear out at a higher rate.
According to posts I've followed most of the folks (and there are only a few of them) that are having problems with the 1DmkIV and/or 1DmkIV+1.06F/W are having issues with older tried-and-true lenses that have worked well for years. Who knows for sure but perhaps Canon didn't adequately test using older lenses whose elements have a little slop (hysteresis) in their movement; of course this is just speculation on my part.
What is not speculation is the issue of vibrations. If you can hear an out-of-place vibration then you can bet the house that your lens is wearing out at a high rate.
The only lens I own that vibrates is my 28-135; the IS servo is chattering only when I make a dramatic move (i.e. a new composition) from one part of the scene to another. Once the camera settles on the new scene the IS vibration comes to a halt (thank goodness). My IS vibration of my 28-135 has been getting much worse over the last three years and eventually I'll have buy a replacement (sob, sniff, it's my favorite walk-about). I'm truly fortunate that the AF mechanism of the 28-135 has no vibration issues, only the IS mechanism has an issue.
I use AI Servo for everything and just lift the thumb to stop focusing. With the Mark II and now with the Mark IV I don't see any difference. The Mark III was a different story and I had to use One shot to get reliable focusing on still targets with that one.
"No, when IS is turned OFF and you are on a tripod with AI Servo AF enabled there should be zero hunting (after initial acquisition) if you keep the shutter button depressed; note, this is true only if both the lens and camera body don't have hardware issues."
Because "guaranteed" was the term you used.
I have my own suspicions regarding all these "problems" with F/W 1.06 but I wouldn't care to speculate about anything at this point (and I own one).
"No, when IS is turned OFF and you are on a tripod with AI Servo AF enabled there should be zero hunting (after initial acquisition) if you keep the shutter button depressed; note, this is true only if both the lens and camera body don't have hardware issues."
No, that (above) is not speculation on my part; it has been confirmed by tests of many camera/lens combinations.
BTW, just so you know ... when I said "guarantee" I really meant it (and I don't use that term lightly). Also, like everybody else I take my turn at speculating but typically try to point out that I am speculating (as versus making a statement of fact).
jkurkjia wrote:
"No, when IS is turned OFF and you are on a tripod with AI Servo AF enabled there should be zero hunting (after initial acquisition) if you keep the shutter button depressed; note, this is true only if both the lens and camera body don't have hardware issues."
No, that (above) is not speculation on my part; it has been confirmed by tests of many camera/lens combinations.
OK where are these MKIV tests?
The MKII is a different camera and no longer relevant.