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Large Dust Donuts
Last night imaged M30 globular cluster with my new 2600MC due to a 60% illuminated moon , captured about an hour of data plus darks ( no filter )
Processed last night and found 2 large dust donuts close together about half way out in the field
So removed the coma corrector thinking it had dust and replaced it with a plain adapter
Adjusted focus again then captured another hour on M30
Processed image and found the original 2 large dust donuts had disappeared but now 2 new dust donuts in a different location in the image but not in the same rotation plane ( camera installed in focuser same orientation as first capture)
Any ideas ?
Surely my brand new camera hasn’t got dust on the sensor ?
Or in the process or cooling and warming the sensor had formed micro evaporation spots ??
Very frustrating
Never had any issues with dust donuts after using my DSLR for 3 years
PS I’ve never needed to take flats
and yes I use a hurricane blower on all my optics before use
Welcome any advice on the weird problem above
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