Hi, I've got a problem that just doesn't seem to go away. I bought a 600D 18 months ago specifically to do animation. I am using Dragonframe software which controls the camera during a shoot with lots of exposures. I am also using manual Olympus lenses with an adapter, so I don't get flicker from the aperture closing down to a slightly different size before each shot. The first sequence I shot was lovely and steady, with no noticeable flicker. But after that I have been getting flicker on all the image sequences. I process the Camera Raw images in Photoshop, and have to adjust the exposure manually for each frame (sometimes around +/- 0.25) The histograms show some noticeable differences, even though the exposure and ISO are supposed to be locked. I thought this was a camera problem, so it has been back to Canon for inspection, but nothing has been found. I am wondering whether I am simply asking too much of a cheap camera to expect it to expose frames the same each time. In the software the histogram moves around constantly, even when nothing is changing in the subject matter. I am generally shooting at 1 sec exposures, using various light sources, so the long exposure should even out any possible fluctuations in power or light. But still the problem persists. Any ideas? Or should I bite the bullet and go and buy a 7D or 5D Mk11?
I should add that the flicker issue was very noticeable when I was using 1/40th exposures, but is still noticeable, perhaps a bit less extreme, when I use 1 sec exposures.
Is there anything in the camera controls that I am missing? I have been through the menus a dozen times at least!
Hi Russell. Thanks for having a go at this. It is a really tricky problem.
The software has a locking button, where you can lock the shutter speed and ISO. It controls the camera operations. Even when I activate this, the image still seems to waver around - I can see the histogram moving up and down and from side to side, indicating varying exposure.
No one so far has been able to answer the question of whether it is to be expected that the histogram should move around - even when all other factors are stable, i.e. static subject, steady light etc. My instinct says it shouldn't, or very little. Canon looked at the camera, but didn't seem to think there was a problem...
I have looked at the original shot, and the control panel does not preserve the original settings. I have looked in the metadata, but this does not help much either. I have also re-read the manual, and this does not indicate any auto-adjustment control. The software is the industry standard for this sort of thing, so is intended to keep your exposures consistent.
I keep coming back to the question of whether the camera should be capable of taking a series of stills at exactly the same exposure levels, or whether it is considered normal for it to have a certain 'fudge factor' which allows it to hunt around? (I have tried taking a series of stills in this way, unconnected to the computer, and still come out with differences from one exposure to the next.) This doesn't seem right to me.
I noticed that on the camera I cannot operate the Exposure Lock when it is in Manual mode. I assume this is normal. But the software manufacturer tells me that the camera must be linked to the computer in manual mode, via Live View, suggesting to me that it might not be able to lock the exposure, if I can't.... In which case, should I be able (i.e. is this intended by Canon) to lock the exposure in manual mode, and would this indicate a fault in the camera? (Of course this last point is irrelevant if the Exposure Lock does not continue from one shot to the next.)
Hmm. The camera has never been operated on Auto mode, as it was purchased expressly for animation, and I don't use it for anything else. But I'll check to see if the histogram wavers around in Auto mode as well as manual.
Not sure how it can be an issue with the framegrabber software, as that just captures the images produced by the camera. It doesn't process them. That happens later in Photoshop or After Effects.
OK. I've had a look at the histogram on the camera, in both Auto and Manual modes, and it seems to be steady - although it is quite a small readout. It certainly doesn't resemble what I see in the software - so that would suggest there is some issue, as you suggest, with the software, or the connections to the computer. I have tried a couple of different USB leads, and they don't seem to have made any difference at all, so do I then contact the software distributor again, as it was a download, not a DVD?