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Why Does My Dark Frame Look Like This?

Started by Chris1, 03/10/2008 11:32PM
Posted 03/10/2008 11:32PM Opening Post
Title says it all. This dark frame was taken with a ST-8XME, 5 minutes @ -35C. Why the gradient? No matter what I do, the 5 minute dark frame looks like this. All was well a couple nights ago-dark frames were normal. Any thoughts?

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Chris1's attachment for post 41202
Posted 03/11/2008 12:59AM | Edited 03/11/2008 01:04AM #1
Not sure why the banding is there? Light leak maybe?
This is what a 5 minute dark at 8°c for my DSI III looks like.

Attached Image:

fblue's attachment for post 120924

[SIZE="Large"][/SIZE][COLOR="Blue"][/COLOR] Floyd Blue grin
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Posted 03/11/2008 02:28AM #2
I'd also guess light leak.

Theres some situations where a big over-exposure
will leave charge in non-imaging layers of the
CCD, and it will make darks like this, but it
should go away in a couple hours. Or will go
away if you warm-up and cool down again.
Posted 03/11/2008 03:23AM | Edited 03/11/2008 03:23AM #3
Here's my 5min dark @-15c with SX MX-716

Bob

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RUSTY845's attachment for post 120928

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