Anyone know a good way to remove wide horizontal banding? I have a Canon 450D which is getting very annoying in that respect. I have tried various camera settings and cooling and it looks like I'll be stuck with fixing them in post-processing. I would think that dark frame subtraction would help as they show up in the stretched dark frames but so far that's a no-go (at least in DSS.)
I had this issue with my 40D and 5D mark II. Not only for astrophotos, but also for daylight images in the deep shadow areas. I suspect that it varies between individual cameras, so some users may never see the problem.
Not all frames had the banding, but when present it was mostly in the red channel. More frames helped. All ISO settings had the problem. Try leaving a longer pause between frames. I ultimately solved the problem by trading in the 5D mark II for a 6D. No more banding even on individual frames.