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Old 29-11-2018, 08:05 PM
Eris
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Another Dark Question

Hi Everyone,
I am about to make up a Library of Dark frames and have a question of how accurate they are when it comes to processing images.
Let’s say for argument sake that I create a series of Dark frames at -20C below ambient temperature at 10 minutes each. Then on an observation night I take a series of Light frames again at -20C below ambient each lasting 10 minutes.
The question is this. If those Dark frames taken at -20C below ambient with a room temperature of 18C be accurate enough when Light frames are taken in a night temperature of 8C? Both sets are taken at a set point of -20C but the starting temperature is different?
Does this difference affect the quality of the Light frame being processed?

Thanks in advance to all who can help me understand this issue more clearly.
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Old 29-11-2018, 08:43 PM
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RickS (Rick)
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You need to take the darks and lights at the same absolute temperature, not at some offset from ambient. Pick a temperature that you can achieve for both darks and lights and then use that as your set point.

Cheers,
Rick.
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Old 29-11-2018, 09:38 PM
Eris
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So if -20C can be reached in both dark and light frames ambient temperature at the time both images are taken is irrelevant?
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Old 29-11-2018, 10:07 PM
brisen (Brian)
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Quote:
Originally Posted by Eris View Post
So if -20C can be reached in both dark and light frames ambient temperature at the time both images are taken is irrelevant?
Correct. As long as the sensor temp is consistent between both lights and darks the ambient temperature is of no consequence. It just means you wont need to use as much of the cooking power to get to the set temp.

Brian
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Old 29-11-2018, 10:44 PM
Eris
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Great!
Thanks for your help guys.
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