Why I didn't see any samples on real world photography from 7D owners.
Why don't you see a lot of sheep with burnt noses from electric fences? Not because the electricity isn't there, but because the sheep stay away. People get burnt with using deep shadows, and they'll avoid them, even though it might be advantageous to use them, if possible. Many people whine that digital doesn't have the highlight headroom of negative film, but it actually does, because ISO 100 on a digital would be ISO 800 or more with film; digital is that much more sensitive. But, since the shadows of low ISOs have been marred by read noise and pattern artifacts, digital cameras have underrated their ISOs (IOW, exposed to the right) to stay clear above the read noise.
Without the patterns, one could shoot ISO 100 at -3 or -4 EV, or set the camera to "sunny f/16" on a bright, sunny day with deep shadow areas, and not worry about too much ugly noise. The first real image I subtracted the vertical offset patterns from, I examined in a shadow area pushed from ISO 100 to about 5,000, and the result didn't look very bad at all. And actually, I didn't subtract the pattern but an untouched blackframe, so I actually increased random noise by 1/2 stop, and it still didn't look too bad. A better subtraction image could be made. I will be demonstrating all this soon, but I have a lot of "real world" shooting to do, despite the caricature often made of me from people extrapolating my personality and activities from the facet of me seen in these forums.
All I saw is blackframe analysis on 7D, but no real world samples
I doubt it is a common issue of 7D
Of course it isn't, because the sheep are well-trained, and limit their possibilities by avoiding the issue.
But, relative to the 5D2, the 7D issue is more minor (on a good copy). The 5D2 banding has a lot of bold, single lines, and that causes color clustering or outright colored lines.
The DR of the 5D2 is more limited than the 7D at base ISO, from what I've seen, but I haven't done a direct comparison yet.
Anyway, I have run into the finiteness of 7D high-ISO capability; in dark green areas, (filiage itself in light filtered and reflected by foliage) horizontal banding is visible at 3200 and above. That started at about 1250 with the 50D, though.
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John
