NGC 104 + data

[alpal]

Originally Posted by Atmos

I cannot think of a reason why the filter wheel wouldn't have moved. I wasn't watching it at the time but it was working at other times, did the flat fields later on without any problems. I cannot think of a reason why the filter wheel wouldn't have been working.

The files that are up have been fully calibrated and aligned. Really not sure what is going on. Tomorrow I am going to start afresh, drop the Gain from 26 back to 21 and then recalculate the Offset, might try 105 or something. If 102 is causing a clip of the lower end of the files then maybe it just needs to be increased. At 102 I am getting ~550 ADU (levels on the bias) so not quite sure.

I wouldn't worry too much about your levels.
Just get more data with your present settings
otherwise your stacks will not work properly
when you combine all the data.

Just make sure that filter wheel is changing.

cheers
Allan

[Atmos (Colin)]

Originally Posted by alpal

I wouldn't worry too much about your levels.
Just get more data with your present settings
otherwise your stacks will not work properly
when you combine all the data.

Just make sure that filter wheel is changing.

cheers
Allan

3x200 RGB should be enough to get colour, half an hour of RGB on a bright cluster should work correct?
I've done something similar, one hour of RGB on NGC 2070 and having the same issue at 200s. I know that if I push it to ~600s it will fix the problem but that is 10x my sky limited.

[SamD (Sam)]

If it helps, I've just run my recent NGC104 through some star ADU counts.

If I scatter plot my blue (y) vs red (x) ADU counts I get a fair amount of spread representing the different star colours. But doing the same with the blue and red fits you uploaded look pretty much identical - so it looks like the same channel has been captured in both.

For globular clusters I set the exposure times in each channel so that the brightest stars at the centre are close to, but not over, the full well levels of the camera pixels.