Re: Cincinnati Status Report - Jan 06, 2002

[Tom Droege <tdroege@veriomail.com>]

Mike,

>As part of the debugging process I've taken some bias images with good
>results.  The readout error (1 sigma) for the two cameras was 5.0 and 5.7
>ADU's which is equivalent to 12.5 and 14.2 electrons respectively.  This is
>certainly well below the error that the background sky will produce at my
>site.  I have noticed that there are subtle patterns in the bias images at
>the level of 2 ADU's.  I am at a loss to explain these patterns, they may be
>interference induced.  At any rate they're in the noise.

You must be running pretty cold.  This is about as good as I have seen for 
noise.  With some care you can detect some cross talk between 
channels.   This was also noticeable in the Mark III.  In the Mark III 
images, you would from time to time see a dark spot in a channel that 
corresponded to a bright star in another channel.  You can most probably 
see this for an image that is coming off saturation when the other image is 
coming out of saturation at a different point, or is not 
saturated.  Roughly I have seen about 1 part in 2000 cross talk.  It is 
usually also in the noise.  There is also some pattern noise.  This should 
be repeatable, so would subtract out with a dark frame subtraction.

Tom Droege