Unfortunately, I was at a client site and didn't have any time to take example photos. The image is quite clear in my mind though. The final focus point was directly on top of the line made by a dark leather chair and the white wall, while the middle sensor was aimed at a lamp on a desk. Wish I had the example photos now. I've been reading about your ordeals with the 35L and seeing how frustrated (not in the British sense) you were. Now I know a little bit of how you felt.
I hate to be without this camera for an extended period, but I think it's about to make a trip to the local Canon USA office.
J. Allen wrote:
You said: "Then, before I could release the focus button and take the shot, another focus point to the lower left of center lit up and I got another beep as the camera shifted the focus."
What do you mean by releasing the focus button? Are you using the AF on button to focus and then releasing it or are you using it to lock focus after half pressing the shutter (is cfn IV-1 set to 1?) and then losing focus? What's your setting for cfn IV-2 which switches the AF ON and * functions? How about III-10? Do you have a registered AF point selected?
The only thing I've set of these settings is IV-1 to 1 so I'm not experienced in playing around with them but it seems to me if it's not the result of opertion in relation to one of the above settings there's a problem with the camera. I think some have found defective sensors when they've had the camera sent in for service. ...Show more →
The * and AF ON buttons are swapped and focus is only with the * button. So, I pushed down on the * button, it focused on the center (selected) focus point and gave the confirmation beep, then just before I took my finger off the button to use the cable release, an outer focal point lit up (right over the line of a dark leather chair against a white wall) and I heard another confirmation beep. The camera was rock steady on a tripod and did not move during this. Second and subsequent presses of the * button caused the exact same behavior with no deviation.
Jeff wrote:
My 1D MkIII as well, but I have seen the 'extra' adjacent AF points light up randomly (usually it doesn't do this, but sometimes it does, for no reason apparent to me). It's one of the things that made me believe that other (assist) AF points are being used, even if they shouldn't be, CFn-wise.
Jeff
PS: Canon's documentation on what these 'new' AF Assist points actually do is sorely lacking. It really makes you wonder what's going on under the hood.
Jeff,
I went back and looked at my AF assist settings last night and they were turned off. However, I had been doing some BIF the weekend just before the shoot and had it turned on then. I'm pretty sure I turned off the assist points before the shoot, but perhaps not. (If not, then they turned themselves off after the shoot because I've not changed any settings since then).
So, if the assist points were activated, there are the horizontal and vertical non-selectable points immediately surrounding the selected focus point that can be used to attain focus. The documentation is pretty clear on that. I also have the choice of activating all of the surrounding points assist points, or just those on line with it. If assist points were on, then I would have been using all the surrounding assist points and not just those on a line. What lit up and acquired secondary focus was an outer selectable focus point, not an assist point. This is definitely contrary to what the documentation says to the best of my ability to understand it.
If what you are getting at is the case (i.e., that I left the AF assist on), and this is linked to the expanded AF points when activated, then it would appear that the AF assist algorithm, and/or the sensor it works with, is broken. That's definitely something to think about. I'll see if I can create a situation where this behavior repeats, and turn AF assist on and off to see if it has any effect.
As a side note - the BIF outing left me absolutely steamed at the AF system. I'd been doing this with a 1DsII with very good results and was very eager to enjoy the increased focus speed and reliability of the 1DsIII. The first half of the morning I would put the center sensor directly on the bird while it was fairly far away and with only the sky as a background. Focus would lock on it immediately. I'd follow it as it got closer waiting for it to fill the frame before firing. However once it got within range, either the ocean or the terrain would enter the frame and the sensor would stop focusing. No matter how many times I let up on the focus button and re-activated focus it wouldn't pick up the bird and it wouldn't shift off its last point of focus. I tried using all point AF, I tried turning on and off AF assist points, I tried screaming at it. Nothing had an effect on the focus (although the screaming got the birds to fly to another area). This was all with the 600L - either on a Wimberly or handheld (I was desperate). I finally switch to the 70-200 and move in closer and managed to get slightly better results, but the problem was still there. grrrr... I had focus tracking less than 20% of the time, and when it did track (or fooled me into thinking it was tracking enough that I would take the shot), I got less than 40% of the images in critical focus - a combined success rate of less than 8%! My total success rate on the 1DsII is usually closer to 70%. While I'm not convinced that there isn't a magic combination of custom function settings that will make this work, I am still searching.
Unfortunately, I was at a client site and didn't have any time to take example photos. The image is quite clear in my mind though. The final focus point was directly on top of the line made by a dark leather chair and the white wall, while the middle sensor was aimed at a lamp on a desk. Wish I had the example photos now. I've been reading about your ordeals with the 35L and seeing how frustrated (not in the British sense) you were. Now I know a little bit of how you felt.
I hate to be without this camera for an extended period, but I think it's about to make a trip to the local Canon USA office.
Unfortunately, I was at a client site and didn't have any time to take example photos. The image is quite clear in my mind though. The final focus point was directly on top of the line made by a dark leather chair and the white wall, while the middle sensor was aimed at a lamp on a desk. Wish I had the example photos now. I've been reading about your ordeals with the 35L and seeing how frustrated (not in the British sense) you were. Now I know a little bit of how you felt.
I hate to be without this camera for an extended period, but I think it's about to make a trip to the local Canon USA office.
BTW, was the lamp turned on... in other words, did it shine (brightly)?
Another thought... I have seen it happen that other AF points than the selected flashed after half-way pressing the shutter release with my EOS 3 and 1Ds3. In case of the EOS 3 even all 45 of them. Usually when it is dark, because in that case the dark VF makes it easier to see this happening. Maybe logical because all the AF points are part of a bigger sensor. But when it happens, focus is still on the selected AF point. I have never seen it jumping to other AF points. So, maybe your body/AF is broken or maybe you witnessed a coincidence: a front-focus issue because of the strong lamp light (or another cause) in combination with flashing AF points other/besides than the selected one (which seem to be a normal thing in itself that is visible under certain conditions - at least with my cams).
As far as the other focus point lighting up in one shot mode I'd send your camera in. I seem to remember someone else having the same problem and it was repaired by Canon. It may have been the * button. I also seem to remember someone noticing that with the registered AF point selection option enabled they would get other focus points lighting up under some conditions but I think a firmware fixed this or disabling the registered point did.
The only thing I can think of with the camera refusing to refocus on the bif is cfn III-5 in AI Servo mode. If it is set to setting 1 - focus search off - and the camera doesn't get focus initially it will just sit there and not focus. I had this happen and I could not figure out what it was until I bought and read Arthur Morris' Mark III Users Guide where he pointed out this issue. I keep it on setting 0 now.
Daan B wrote:
BTW, was the lamp turned on... in other words, did it shine (brightly)?
Another thought... I have seen it happen that other AF points than the selected flashed after half-way pressing the shutter release with my EOS 3 and 1Ds3. In case of the EOS 3 even all 45 of them. Usually when it is dark, because in that case the dark VF makes it easier to see this happening. Maybe logical because all the AF points are part of a bigger sensor. But when it happens, focus is still on the selected AF point. I have never seen it jumping to other AF points. So, maybe your body/AF is broken or maybe you witnessed a coincidence: a front-focus issue because of the strong lamp light (or another cause) in combination with flashing AF points other/besides than the selected one (which seem to be a normal thing in itself that is visible under certain conditions - at least with my cams). ...Show more →
The lamp was turned off. But you raise an interesting point - since this was a very wide angle lens, and set to f/8, I have to admit that I have only assumed that the focus shifted to the new focal point just before it lit up and beeped. The depth of field would have been so great that I doubt I could tell the difference between focus at either focal point. If I garbled that last sentence too badly, what I mean to say is that either focal point would have been well within the depth of field of the other. I wouldn't have been able to confirm that the focus itself actually did shift - only the focal point.
J. Allen wrote:
As far as the other focus point lighting up in one shot mode I'd send your camera in. I seem to remember someone else having the same problem and it was repaired by Canon. It may have been the * button. I also seem to remember someone noticing that with the registered AF point selection option enabled they would get other focus points lighting up under some conditions but I think a firmware fixed this or disabling the registered point did.
The only thing I can think of with the camera refusing to refocus on the bif is cfn III-5 in AI Servo mode. If it is set to setting 1 - focus search off - and the camera doesn't get focus initially it will just sit there and not focus. I had this happen and I could not figure out what it was until I bought and read Arthur Morris' Mark III Users Guide where he pointed out this issue. I keep it on setting 0 now. ...Show more →
According to to the Canon USA web site, I have the latest firmware for this camera, however what you say gives me hope that this is fixable (unlike the 1DIII, it appears) and may have a well defined cause. I'll be turning it in to them this coming Tuesday, so we'll see how it goes...
re: C.Fn III-5:0, yep - I learned this one the hard way too. Unfortunately, I still haven't found a combination of settings that lets this thing focus on BIF any where near as reliably as the 1DsII .
Daan B wrote:
Another thought... I have seen it happen that other AF points than the selected flashed after half-way pressing the shutter release with my EOS 3 and 1Ds3. In case of the EOS 3 even all 45 of them. Usually when it is dark, because in that case the dark VF makes it easier to see this happening. Maybe logical because all the AF points are part of a bigger sensor. But when it happens, focus is still on the selected AF point. I have never seen it jumping to other AF points. So, maybe your body/AF is broken or maybe you witnessed a coincidence: a front-focus issue because of the strong lamp light (or another cause) in combination with flashing AF points other/besides than the selected one (which seem to be a normal thing in itself that is visible under certain conditions - at least with my cams). ...Show more →
ChillAloha wrote:
The lamp was turned off. But you raise an interesting point - since this was a very wide angle lens, and set to f/8, I have to admit that I have only assumed that the focus shifted to the new focal point just before it lit up and beeped. The depth of field would have been so great that I doubt I could tell the difference between focus at either focal point. If I garbled that last sentence too badly, what I mean to say is that either focal point would have been well within the depth of field of the other. I wouldn't have been able to confirm that the focus itself actually did shift - only the focal point....Show more →
From reading that topic, I would tend to say that this is a different phenomenon. This isn't any kind of ghosting, rather a single focus point lights up (definitively) and a second focus confirmation beep occurs. This I can confirm. The only thing I couldn't confirm was whether or not the lens focus elements were actually moved to a new position within the lens.
My 1DMKIII will also choose to light up another point at random. I have the focus point set to always stay lit while the back focus button is pushed and sometimes...dont know just why...another point lights up and they will both stay lit.
Doesnt do it all the time and when it does I reset focus. Sometimes it keeps doing it a few times but eventually it stops. I just got it back from Irvine about 3 weeks ago where they found the focus was well out of tolerance and also apparently the flange for the lens was not square. This was a blue dot. Just now having time to check it out and see if its any better.
ChillAloha wrote:
From reading that topic, I would tend to say that this is a different phenomenon. This isn't any kind of ghosting, rather a single focus point lights up (definitively) and a second focus confirmation beep occurs. This I can confirm. The only thing I couldn't confirm was whether or not the lens focus elements were actually moved to a new position within the lens.
OK, good thing I double checked this with you. So it is safe to say that what you are experiencing isn't "normal" by any means. Maybe you can try to simulate the whole situation and shoot at a wider aperture to see if focus has indeed moved at all. In any case, I think I would sent it off to Canon Service
Thanks everyone for your comments and help. I turned it in to Canon USA in Honolulu today and will let you all know what they have to say when it gets back.
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