M33 part 1

[RikM]

This autoguiding business certainly opens up possible imaging targets doesn't it? I had a quick go at this one with unguided 90sec subs a little while ago and just couldn't pull it out of the LP.

I had plenty of clouds to contend with and a meridian flip so this was all a good learning experience. I tried to grab darks here and there when clouds were being bothersome. The results so far mean I am going to put the next few clear nights into this target to see what a few more hours will do for the detail and smoothness.

In DSS I had to put the pre-flip subs in group 1 and the post-flip subs in group 2. (When I loaded them all into the same list, the stack ended up as a superimposed double image with an offset of 15 pixels or so???) Is that normal?

This is 9x600s @ ISO800; 7x darks; 51x flats; 51 bias.

Obviously it needs a load more data and more darks. It feels a bit 'flat' and lifeless. I can't increase the contrast without increasing the noise. Will more subs allow me to do that? Should I stick with 10min subs? Longer / shorter? I think I will do a run of 3min subs for a star layer. I seem to get much better star colour with shorter subs.

What else do I need to work on to improve it?

[AstroLuke]

Do you mind me asking why you made so many bias shots?

I think you have gotten quite alot of data out of your 90 minutes of data, at least compared to how much i get from 60 minutes of data.

[RikM]

Not at all Bias frames are quick and getting loads of them means you have a nice 'representative sample' for the calibration. Someone said that DSS works best with odd numbers of frames. Don't know if that's true ???