Black star/rings next to the real stars after Integration

[Graham]

Howdy,

Before I go of on a tangent thinking that this is a Star Alignment issue, does any one have any idea what would be causing the black circles/stars next to the white stars in my images once I have integrated them. 

A sample is below.

Thanks,

Graham. 8)

[Philip de Louraille]

Did you look at all the frames manually? One hypothesis: you have a double exposure on one frame.

[Alejandro Tombolini]

...or maybe you have integrated frames that are not aligned.

Saludos. Alejandro.

[pfile]

try loading them all into blink and see if one or two are funny.

[Graham]

Howdy.

I have tried all of those things and I cannot say for certain that I can see them in the raw frames. If they are in the raw frames, would that be RBI? The camera is a QHY9 about 3 years old.

Graham.

[Cyclop_si]

Try with "clamp" search on QHYCCD forum... you might get some ideas there. Clamp settings in your driver parameters should most probably be "OFF".

[Graham]

Hi Cyclop,

I will double check that, however it should be off.

I took a heap of SII frames also, undithered. I will see how those have turned out.

Thanks for your thoughts,

Graham