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Old 23-12-2011, 03:56 PM
TrevorW
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Qhy8

The latest image shows banding refer attached

any clues what may be causing this

this is a stack if 12 auto levels only applied captured using Maxim, stacked DSS, no darks or flats

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Last edited by TrevorW; 23-12-2011 at 04:14 PM.
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Old 23-12-2011, 05:28 PM
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mithrandir (Andrew)
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Trevor, is this is what you mean? I see bands along the edges caused by stacking when the frames do not match exactly.

I don't know about DSS but Nebulosity logs how many pixels you need to crop off to get rid of the edges. You need to do this before any other colour/brightness correction because those edges screw up the algorithms.
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Old 23-12-2011, 06:24 PM
TrevorW
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Right side and bottom of image never seen this before

stacked in DSS, I ran some other frames I did a while ago and they are fine, so it's got me beat

I did notice that the Dx dy numbers for the first 5 frames in the stack differed from the rest
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Last edited by TrevorW; 23-12-2011 at 06:45 PM.
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Old 23-12-2011, 07:00 PM
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mithrandir (Andrew)
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Quote:
Originally Posted by TrevorW View Post
Right side and bottom of image never seen this before
It will also be on the left and top but is not as noticeable.

Quote:
I did notice that the Dx dy numbers for the first 5 frames in the stack differed from the rest
That is what I suspected. I'd guess the mount got bumped between frame 5 and 6. You can either crop 106 pixels off left and right and 71 from top and bottom, or only use the first 5 or last 7 frames if you want the whole field.

It is not unusual to have to crop a few pixels.
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Old 23-12-2011, 08:23 PM
TrevorW
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Thanks Andrew I've not had this happen to me before so I thougt it may have been the camera as I had some recent problems with it

Meery Xmas
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