Looks like my cam has 62 bad pixels in 54 clusters and my calibration picture doesn't show heavy banding.
Are you sure about the banding? I'm
guessing you may be a bit overly optimistic, but I cannot be sure ofcourse. You did the image processing. Why do I think you might be too optimistic about the banding? Two reasons:
First, the bad pixels in the first image are really dark. So I am guessing you are looking at greyscale stretched values from lowest to highest, without doing something about the raw values of those bad pixels. If you look at my pictures waaay back, then you'll see that the bad pixels are medium grey. That's because I substituted the median value to bad pixels. That way they do not mess up the normalization.
And second, you
do get correction terms that have banding in it. That alone tells me that there is correction being done for banding in the underlying raw values.
If you're interested you could PM me your two files for calibration + correction, so I can run it over here as well as a comparison. That, and it gives me an excuse to improve the bit of code I have to process cal + correction images. Right now it's crap.
Edit: Oh yeah, and third reason I think you really get more banding is that your first pic doesn't show enough vignetting. You could be lucky and get a really good sensor with almost no banding. However getting a magic lens that doesn't show roughly the same amount of vignetting as on my pics would seem unlikely.