Weird D2H long exposure problem
In reviewing some pictures taken recently with my D2H, I have found that I am having a weird problem during long exposures at night. It only seems to happen in exposures longer than ten seconds, and only when there are bright light sources in the frame somewhere. The problem shows itself as magenta colored 'fogging' in the lower corners of the picture, or in the right-most corners of a vertically oriented picture. I have seen the result with 3 different lenses (12-24dx, 28/2 ais and 50/1.8 ais), all with similar results. It looked like some sort of flare, so I didn't notice it at first, but I have seen it in several different shooting sessions, all under similar conditions as described above. I am not 100% certain, but I believe it has happened both with and without the long exposure noise reduction turned on.
Anybody have any issues along these lines with their D2H or other D series Nikon Body?
#1. "RE: Weird D2H long exposure problem" | In response to Reply # 0Chippypete Registered since 16th Aug 2012Sat 03-Nov-12 09:59 PM
It sounds like shutter curtain isn't sealing properly when it drops back into place which in turn causes overexposure in the area where it isn't light tight. I had this problem in an old Olympus film SLR, it was that bad that all photos had a red corner no matter how long or short the exposure was. It could be damage to the shutter or just something getting in the way of the shutter fully seating.
#2. "RE: Weird D2H long exposure problem" | In response to Reply # 0blw Nikonian since 18th Jun 2004Sun 04-Nov-12 07:22 AM
> Anybody have any issues along these lines with their D2H or other D series Nikon Body?
It happens with just about all digital cameras, actually. What you're seeing is thermal buildup, and it happens more in the cold than in hot weather.
On a D2h, the typical fogging is a kind of pinkish thing, generally in the lower right corner of a landscape-format image.
> I am not 100% certain, but I believe it has happened both with and without the long exposure noise reduction turned on.
I'm pretty sure it doesn't happen with LENR, because that is exactly what the feature is designed to address. What it does is to capture your image as specified. But then it closes the shutter and takes another frame of equal duration. Since the shutter is closed, this frame should be completely black - every pixel should be 0,0,0. But it's not, because of the thermal problem. So then the camera subtracts the dark exposure from the original. (Actually it subtracts a derivative of it, since the thermal buildup pattern is known, and the end of the 2nd exposure is subject to much more thermal buildup than the beginning of the original one.)
Brian... a bicoastal Nikonian and Team Member
My gallery is online. Comments and critique welcomed any time!