p.35 #8 · ['NEW Fix' UPDATE!] - MkIII AF still broken
Alistair Watson wrote:
Do I win a prize Jeff? Do I win a prize?
BTW I love my bike too!
And yes, before you ask, those are time trial bars on my mtb, an unusual hangup from my road racing days....
This has obviously gone way off topic, but I'd love to see you belting down an off-road downhill track using the TT bars!! Why haven't they cottoned onto this in the Olympics?
p.35 #9 · ['NEW Fix' UPDATE!] - MkIII AF still broken
andrewd01 wrote:
This has obviously gone way off topic, but I'd love to see you belting down an off-road downhill track using the TT bars!! Why haven't they cottoned onto this in the Olympics?
Don't use the TT bars off road, I probably wouldn't make 10 metres before heading off into the nearest thicket or ditch! I just like scaring the 'roadies' every so often when I go speeding past [on the road], almost always get a double take when they see the bars and it is actually a really comfortable and powerful position to ride in. Try it!
p.35 #13 · ['NEW Fix' UPDATE!] - MkIII AF still broken
craig_oz_land wrote:
Sorry guys don't have time to read the whole thread and I don't own a MkIII so apologies if it has been mentioned already.
I do know that focus varies depending on the light source with the 20D. I went through quite bit of this when finding focus variability on a 20D. It turned out that natural and man made lighting caused the AF to front or back focus differently and consistently with the different light sources. This was also confirmed by others.
Here also is a link on the technical workings of Canon's AF system.
Thanks - this is a good article that ought to be re-read every once and a while. Good theory - btw I think the Sigma observation is consistent with my experience - which is, if one focused on a distant object (e.g. 100m) and then focuses on a closer one(1m) , the AF system would tend to backfocus a bit, while if one focused on a closer object (e.g. 0.5m) and then back to (e.g. 1m), the system tends to front focus a bit. The theory also predicts the observation that the problem would be worsened if the sensor area is larger or has more horizontal slop than is indicated by the markings on the viewfinder.
Just had a whole bunch of lenses back from Canon Service Hong Kong. Everything is a bit better than before but far from 'true', with front/back focussing detectable even just looking at the back of the LCD zoomed in. The front desk lady insists that they are 'within-spec', but some of them still look pretty marginal to me. (Although to CS HK's credit they didn't really complain when I asked them to re-do some calibrations).
Canon really needs to improve the control/consistency of the AF system. 6x9" -1/10 seems a bit sloppy especially given people's increasing tendency to print larger and looking at 100% crops. That Canon is not trying to 'kaizen' this just seems very...un-Japanese, for lack of a better word.
Does anyone know if Nikon/Olympus/Medium format manufacturer AF specs for accuracy are better/worse? What's the point of getting AF or fps really fast when the accuracy is off this much?
Edited by Levendis on Jan 28, 2008 at 07:30 PM GMT
p.35 #14 · ['NEW Fix' UPDATE!] - MkIII AF still broken
May I ask what battery level you are testing at? On Saturday night, I finally drained my first Mark III charge down into the 'blinking' zone. (below 10%) I noticed that my camera performed quite sluggish - it hunted with my 70-200 for the first time I've owned the camera in a week and with about 2,300 actuations under the battery's belt. When I noticed that I was consistently missing shots and getting OOF frames, I found myself frustrated and could relate to some of you on here with defective units. I immediately changed the battery with a fresh one and found the camera to perform infinitely better. With the low-life battery, I seemed to get 1 or 2 properly-focused frames out of a burst of, say, 6 or 7 frames. I can usually shoot 10-12 and maybe get one or two soft frames on a normal night, but most or all are acceptable after sharpening and post-processing.
Just thought I'd bring this issue up as I am a new 1-series owner and thought I may seek some assistance or possibly stir up some new thoughts on an issue that has caused many headaches on this forum.
p.35 #16 · ['NEW Fix' UPDATE!] - MkIII AF still broken
Jeff wrote:
My lenses used to work just like lenses are supposed to: you put the little red dot on something, press the button, and it focuses. Voila! Like magic. I shouldn't have to spend $600 to calibrate my previously working lenses so that they work on the MkIII.
I hope it will prove to be this way with your other lenses.
Jeff wrote:
I feel like someone's got a little voodoo camera doll, and is sticking pins in it as I repeatedly jump through hoops like some pathetic monkey in a zoo...
This is exactly the fear the prevents me from getting a 1D Mk III. In the mean time I have added a 10-22 to my 40D and 17-55, BG-E2N and EF-S focusing screen are on the way. The 1D Mk III keeps getting further and further the more you post.
p.35 #17 · ['NEW Fix' UPDATE!] - MkIII AF still broken
k1n3t1k wrote:
May I ask what battery level you are testing at? On Saturday night, I finally drained my first Mark III charge down into the 'blinking' zone. (below 10%) I noticed that my camera performed quite sluggish - it hunted with my 70-200 for the first time I've owned the camera in a week and with about 2,300 actuations under the battery's belt.
I experienced similar with my 5D at an air show last September. I was shooting with the 300/2.8 IS and 1.4X, but I left the battery grip at home. By the end of the show, it was starting to hunt and miss focus. Turns out that the battery was way down, probably due to driving the IS over long periods of time as I tracked the moving aircraft with the shutter button halfway down.
I usually put the grip on for long shoots, and this confirms my need to do so. Obviously, the grip/no grip issue doesn't exist for the 1D3, but I can see a low battery having an effect on performance.
p.35 #19 · ['NEW Fix' UPDATE!] - MkIII AF still broken
Yakim Peled wrote:
This is exactly the fear the prevents me from getting a 1D Mk III... The 1D Mk III keeps getting further and further the more you post.
I am sorry for that Yakim, and have to admit that the 'voodoo doll' was probably aimed at my 50/1.4, which I'd like to throw out the window (with the MkIII). FWIW, the AI Servo sequences from this new camera really are exceptional; I shot a few with the 40D yesterday just to see how it did, and it (sadly) performed similarly to my old MkIII, making my Blue Dot shine like the sun.
I'm currently in the process of calibrating my 24-70 and 70-200, though it's much less simple to do than I'd like. Multiple focal lengths, different focusing errors at different distances, somewhat inconsistent results... It all adds up to a lot of randomness in the process, though I question whether Canon's results would be much better, based upon the results of more than a few around here.
I guess I just don't get why this whole AF thing has become so much more complex than it ever was with my 1Ds. Just because we have the AF Microadjustment capability shouldn't mean that it's now a requirement to get good results (although maybe that is the reason the function now exists?). I'm not yet convinced any odd results with my current MkIII are not potentially of the 'user error' type, but I'm also not yet ready to concede to that until I've done some more investigation. I've still seen no 'ghosting', but have had some odd 'focal plane' effects with a few shots, and that makes me a bit nervous.
Anyway, at least you are spending money on longer term investments this way!
p.35 #20 · ['NEW Fix' UPDATE!] - MkIII AF still broken
gerov wrote:
Jeff,
that looks like a fantastic trail,and the bike is nice too But it doesn't look like you had broken a sweat yet
That's up a canyon a few miles from my house, taken about 1000 feet above the trailhead (it's an 18 mile loop with 2500' of climbing). I was riding with my better half that day, who isn't quite as into mountain biking as I might like. We had a great ride, though...
