Removing focal reducer yields *more ADU?
Hey there,
I was just going through some test data I shot with my RC10.
To get the native focal length of the scope I took a frame without the focal reducer in place (Telecompressor CCDT67).
When I looked at the statistics, the shorter focal length image (the one with the field flattener) captured less ADU than the one with; 787 ADU Vs 923. All variables were otherwise the same.
Seems counterintuitive that a slower system should be, erm, faster?
Weird.
I'll test it again when I get the opportunity to verify - this was based on two individual 1 sec exposures.
It could be anomalous short exposure response of the 1600.
Markus
|