[Shiraz (Ray)]

Hi

Quick heads up. have been stacking large numbers of fairly short subs and stretching very heavily to go deep - it looks like the 32 bit floating point representation in PI does not have enough precision to do this properly (!!) and rounding errors show up in the histogram. Haven't investigated in any depth and am not sure if it is a major issue in most images (they are eventually converted to JPEG), but, since it is not hard to do, suggest that it may be a good idea to consider using 64 bit FP for "average" stacked data with this camera - everything else can stay as is and the histogram errors go away. EDIT: this is probably not necessary - see later post.

The other thing is that median stacking is not a successful option for deep imaging with this camera due to the bit filling process used to extend from 12 bit to 16 bit data - average stacking can fill in the histogram to any desired depth, but the median value of a stack will retain the structure of the original data - with the bottom 4 bits all zero..