[Aavso-photometry] Linearity test puzzle

[Michael Koppelman]

I do get ghosting on bright stars. Usually I sit on the same field  
for hours and if there are bright stars in the field (bright being  
relative to exposure length) I see them on my darks for 5 minutes or  
so. I've wondered whether this indicates a problem with my CCD. I am  
currently testing an ST-7XME (I own a ST-7XE) and they both do it.

Michael

On Jan 26, 2006, at 6:54 PM, M Newberry wrote:

> It also takes electronics working properly to transfer charge  
> efficiently so, a modern CCD showing ghost images is either likely  
> to be on the verge of death or the electronics are not clocking the  
> array in the optimal way.