Aurora Photography - lessons and learnings

[conropl]

I had the same problem when I bought my 7D, and was REALLY upset about it because I didn't know if I would be able to return it. I did some reading and found that running the manual sensor clean option for a minute or two most times fixes the "dead" pixels. The regular sensor clean didn't fix the issue for me, but when I did the manual sensor clean and let it sit for a couple minutes, then turned it off and back on, my hot pixels were nice and black. Maybe give it a shot on yours.

I tried that, and it did nothing. The other problem I have is that there are so bad pixels right out of the box, and by performing the "re-mapping" process, I believe all you are doing is turning them off. I could send it to Canon, and they would map and turn off the offending pixels, or I can swap it out for a new one. I chose the new one because it is easier. You will get dead/hot pixels over time, and I expect it; but I do not want to start with 70-100 coming out of the box and then it only gets worse from there. And sending it to Canon and being without a camera that long did not appeal to me. There was also a drop of oil or water vapor inside the view finder that has since disapeared to somewhere inside the camera.

Would you predict the distortion from the ISO charts? look at the box/lines and the corners of the box might give you a preview of the radial smear.- there is some pretty weak quality wide open a even at 2.0 on the corners. Just my two pennies.

I do not think the 24 looked that bad in the corners on a full frame stopped down one stop in the charts (I will look closer though). I am not sure whether this is a lens issue or a sensor issue. I will be picking up a new camera today after work, and I will find out from there. If it does prove to be a lens issue, then I will have to start investigating it. If it is normal, then I will have to decide if I want to live with it or not. It is really kind of ugly, and would be very noticble if I printed at 16"X24".

Are you seeing coma? I've heard it is common on wide angle lenses shot wide open.

Coma wide open is bad, but once you get to f/2 it cleans up nicely. I assumed I would need to stop down one stop anyway, so I think it looks good as far as coma is concerned provided it is stopped down that one stop.