I have an Atik 490ex with an EFW2 filter wheel and today decided to run the flats calibration wizard.
I’m using LRGB/Ha/OIII/SII filters.
So I placed the flat-box in front of my scope, and with the default settings (30000, 500 tolerance, 0 min, 0 max) i noticed it started with a 5-second image through Lum. This was obviously too bright, so i observed how the next image was around half the current exposure time… still maxed out, but so far so good.
After 10 exposures it was still too bright, so SGP cancelled the run.
I thought to myself “ok, it only attempts 10 times and then cancels… makes sense so let’s lower the maximum exposure time”.
Setting it to 0.01 through Lum worked for the 1x1 binning (after a few attempts that showed 0.00 as the third digit is never displayed), however when moving to 2x2 binning I always got an error message “time above maximum” after a few attempts. I was a bit confused, because this happened after SGP dropped the exposure times a few times already stating the first images were too bright, so it was definitely below my set maximum of 0.01 seconds.
When going through the other filters, i have noticed that i got this error more often and it seems it always happens, when there was an attempt that resulted in an image below the set ADU.
So let’s say I set it to 30000 with a tolerance of 1000. 0 min and 0.01 maximum exposure time through Luminance
SGP starts imaging for 0.01 second and gets a result of 65000 ADU.
It then drops down to about 0.005 (which is just shown as 0.00 due to the third digit not showing) and gets to lets say for this example 40000 ADU… so far so good
It then again drops exposure time again i.e. to 0.002, however this time lets say it reaches 28000 ADU. Now it will stop stating “time above maximum” even though it’s far below the manually set 0.01 seconds. It will not attempt to try making a new image with a higher exposure time to get closer to the 30000 ±1000 tolerance.
I assume this is a bug?