Re: Saturation Improvements

[Tom Droege <tdroege@veriomail.com>]

Andrew and all.  That is my point, in Surface Full Well, some of the charge 
is recombined and lost.  So you may not be able to just sum all the charge 
in the area assuming that it has overflowed from the saturated 
point.  Errors can be 35% from top to bottom.  OK, I have now adjusted the 
VVH so that it is hopefully in Bloomed Full Well, where possibly more 
charge is conserved.  But I would not count on 100% charge conservation.

>When I did this, 'way back when, it emerged that most of the
>overflow charge ended up in adjacent pixels. A reasonable
>estimate could be obtained by summing all connected pixels
>above background regardless of how far the charge had wandered.
>The scatter was a good deal worse than for non-saturated
>bright stars and there was IIRC some evidence of charge loss for
>the very brightest. But the method did gain several magnitudes
>in dynamic range.


Tom Droege