Maximum Exposure Time for Digital Rebel

Hi,

I know this sounds like a silly question, but can a digital rebel do exposures longer than 30s ?

Doug

Yes, in Bulb mode it will open the shutter for as long as the battery will last.

okie, thanks !

Or as long as the two batteries in the grip will last. Or you could use the A/C adapter to go even longer... But realistically your shots will have so much noise in them you won't have any keepers. I've done one hour exposures of star trails and ended up with too much noise. Even 15 to 30 minutes will get excessive. What are you thinking about doing?

Here's a one hour long shot. Note all the noise...

Jon; are you sure these are nose? Couldn't they be those alien watching you from their secret UFOs <{:+). That crazy pilot, was not aware of you taking the image or wanted to create a near meteorite feeling for your image.

Doug if you use long exposure, remember to utilize the assistance of wired remote control.
You may want to get yourself familiarized with "Mirror lock up" procedure and self timer (2 second or so) to reduce internal camera's vibration. Why did I say wired remote?
1) Cheaper
2) You don't want to deal with 2 batteries issues....

Samsen.

Thanks for the tips. I was aware digital camaras didn't perform well under low light but damn, that's some of the most awful noise I've seen.

Are these caused by dead pixels ? Is it possible to mask it out in photoshop doing a long exposure of something completely black (say, the lens cap), or do the positions change ?

No to dead pixels.
Yes to masking it out like that.

Yep, lots of noise! No dead pixies... But that shot was taken in the dark of night and the exposure is 1 hour long. I could try to clean up the image but that's not what I want to do with every shot I take. A better choice for this kind of stuff is to take several images with much shorter exposure times and then stack them in Photoshop or another program designed to do image stacking. What you may want to do could be different though. That's why I asked what you plan on doing with your long exposures.

Here's another shot taken the same night and position at 10 minutes.

Interesting. Could you elaborate on this technique ? Stacking them with the "screen" filter ?

Also, don't forget the eyepeice cover, to stop any extra light getting in that way...