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07/27/2006 05:03:45 PM · #1 |
Ok, I've recently purchased a 30D (now 3 weeks old) and using the Canon 50mm 1.8.
With the "remote" shutter trigger..I left my camera on tripod at 100 ISO, the room temp approx 70 degrees non humid area, with only a small candle for light, for about 7 minutes.
When I returned and viewed the exposure and zoomed in a little there was a lot of noise and white spots all about. I have read that these may be "hot spots". (This shot was also taken with the Custom Settings function for noise correcton.)
Is it a defunct sensor that I have or do ALL digital SLRs have this problem? and if all cameras do have this prob - How are very LONG exposures captured with quality (e.g., showing a pic of the night sky with the stars and the light trails?)
What equipment is the norm for this type of photography..
Any suggestions without the use of any post production software to correct-- |
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07/27/2006 05:34:45 PM · #2 |
| Those are hot pixels, and the behavior is normal. The long-exposure noise reduction should eliminate the worst of them (the bright ones that always are in the same position). If your camera did not take double the exposure time, then the noise reduction was not in play. It works by "subtracting" a second, dark (shutter closed) exposure of the same length from the first. |
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07/27/2006 05:36:21 PM · #3 |
| Removed duplicate thread; let's keep discussion in one place :-) |
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07/27/2006 05:51:27 PM · #4 |
Indeed, as kirbic said, you may want to confirm that the noise reduction is actually working. Also as mentioned, you can tell that it is working if, after a long exposure, the camera processes for the same length of time as the shot before finally saving it. If noise reduction really is working and you're shooting at 100 ISO, the noise shouldn't be that bad. Any remaining noise can be taken care of with Noise Ninja or Neatimage. For Night Shot III, I took a 31 minute exposure out in Joshua Tree National Park with my 20D (ISO 100, with Noise Reduction function turned on) and had minimal noise (not really any hotspots). Talk about a pain in the ass waiting for another 31 minutes for the noise reduction to do its thing... ;)
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