Imaging Comet Johnson

[SteveA]

Hi all..

Okay so first thing...I've never imaged a comet before, usually restrict myself to DSO's, but I thought I might have a go a t this, particularly as its so well placed at present.

I had a quick play last night and caught half a dozen 120 second subs and wasn't particularly impressed! Not tried stacking these yet, but before I return to this tonight (hopefully) I wondered what the advice is on exposure times? I'm using my 10" f4 Newt and the comet head is fairly large in the frame of my Atik 314.

Steve

[Craney]

I'm in the same boat as you.... albeit with a 6" F4...     I would be interested in how experienced imagers cope with the shift of the comet amongst the stars.

Is it better to go for a one-shot attempt ??  as a stacked approach will definitely lead to a smudged result if the subs add up in terms of the total time.

Looking forward to the replies......

 

Sean

[Davey-T]

Just now, Craney said:

I'm in the same boat as you.... albeit with a 6" F4...     I would be interested in how experienced imagers cope with the shift of the comet amongst the stars.

Is it better to go for a one-shot attempt ??  as a stacked approach will definitely lead to a smudged result if the subs add up in terms of the total time.

Looking forward to the replies......

 

Sean

DSS has a comet stacking mode.

Dave

[SteveA]

I use PI for my processing and I see there is a comet alignment module within PI, so looking forward to playing with that.! I have a mono setup and it's inevitable that I'll need to stack anyway. But what I was mainly interested in, was the sort of exposure times I could get away with? Clearly the comet is moving against the background...at what exposure duration does that impact the image its self ? Clearly over the duration of hours/days there is a big shift and for an LRGB  integration that's an important aspect, but in a single sub is there a cut off duration?  I suspect that it's a fairly academic question anyway, as at 120 seconds the comet nucleus was already appearing over exposed compared to the tail. Still interested to hear how the experts approach this though.

Steve