D60 Bulb exposure problems

[Hockey100]

I recently was backpacking and took a 15 minute exposure of Mt. Rainier. I recieved great star trails but....the right side of the frame had a distinct "pink" (looks like when you put a magnet next to a TV) cast that ruined the shot. Not to mention the noise level was out of control at ISO 100. There would be no way I could blow this shot up past a 4x6. There were hundreds of looked like dead pixels. This camera has been flawless during daylight hours. I am willing to email the pic to anyone who could help me solve this problem.

[ddduane]

I have the exact same problem with my D60. Coincidentally, the first time I saw it I was shooting Mt Ranier at midnight! I have since duplicated this "characteristic" at several other locations. If I keep the exposure under 3 minutes, things seem to be pretty good. I've considered taking several 3 minute exposures and stacking them in Photoshop to dublicate a longer exposure, but I haven't actually tried it.

I'm curious whether the 10D has this same affliction.

[henkbos]

I've read about this problem in the D1 and the D60 was supposed to be better. The pink is caused by the heat of the sensors. Canon recommends not to use the camera continuously, but switch it on just before taking the picture.

[Guillermo Freige]

I think a 15min exposure is too much for the current level of digital imagers. Probably a 3 to 5min limit is a good idea. I saw 5min exposures without too much noise. Also a "cold" camera and a cold weather will reduce the dark current noise level, so try to use a just powered on camera.

[daveh]

The long exposure digital photographs taken by telescopes usually use liquid nitrogen or helium to keep the sensor cool. (Not that I'm suggesting that you try this at home.)

[Hockey100]

Thanks for the help guys