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TrevorW
23-12-2011, 03:56 PM
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

:question::shrug::thanx:

mithrandir
23-12-2011, 05:28 PM
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.

TrevorW
23-12-2011, 06:24 PM
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

mithrandir
23-12-2011, 07:00 PM
It will also be on the left and top but is not as noticeable.

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.

TrevorW
23-12-2011, 08:23 PM
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