| Author | Thread |
|
|
03/11/2006 11:56:55 AM · #1 |
hi
(only)in long exposure pics there are always pixel artifacts, which are really distracting. my question is: which part of the camera (sensor? chip? lens? ...) bears the blame for that artifacts? and how can i reduce this effect?
thx in advance for your help!
here's an example (outtake from my "painting with light" submission):
Message edited by author 2006-03-11 12:19:24.
|
|
|
|
03/11/2006 12:01:21 PM · #2 |
They are "hot pixels." It's the sensor that is at fault. Look in your camera manual, if your camera offers a "long exposure noise reduction" feature, enable it for this type of shot. What this feature does is to take a second exposure with the shutter closed and subtract it from the first. It will pretty much kill all these spots, but it doubles the total time required for the shot to be processed. Not all cameras offer this feature, not sure if yours does.
|
|
|
|
03/11/2006 12:11:58 PM · #3 |
no, my "good-old-oly";P doesn't offer this feature...;(
could it also be a problem with the iso value?
and why does this only comes with long exposures??? |
|
|
|
03/11/2006 12:26:42 PM · #4 |
They may or may not show up more at higher ISO. The sensor keeps track of how much light has hit a certain pixel by accumulating electrical chearge. The hot pixels are caused by charge "leaking" into the affected pixels, and the longer the exposure, the greater the leakage. Higher ISO amplifies the sensor signal more, including both the desired signal and any "artifacts" but the short exposure required may offset this effect.
|
|
Home -
Challenges -
Community -
League -
Photos -
Cameras -
Lenses -
Learn -
Help -
Terms of Use -
Privacy -
Top ^
DPChallenge, and website content and design, Copyright © 2001-2025 Challenging Technologies, LLC.
All digital photo copyrights belong to the photographers and may not be used without permission.
Current Server Time: 09/19/2025 05:00:34 PM EDT.
