Comet Lovejoy 9th Jan 2015 / Tips for tail detail?

[dylan_odonnell (Dylan)]

Here is one of my images of the comet of the moment. I've never imaged comets before so I'm a bit lost.

If I guide on the comet I can stack many exposures but get star trails.. if I stack on the stars I get a blurry comet. The magnification is quite high (9.25" SCT with f 6.3 Focal Reducer) so I can't push the exposures too long before the comet has moved significantly.

Obviously no flats in this stack of 4 x 60s subs .. I did use darks.. stacked in nebulosity. But what else can I do to get some contrast and detail between the tail and the sky? Any advice for my next session (or making the most of data I have?)

Thanks in advance!

Dylan.

[PeterEde (Peter)]

DSS allows you to select on which to stack
Startrails is the more appropriate I think.
I've been doing 30 x 60sec

[raymo]

Lovejoy is surely bright enough with your biggish scope to allow tracking the stars for 30 sec subs, and getting sharp stars and comet. I used ISO 1600. I took a 90 sec sub at ISO 6400 with no sign of a tail, so it must be extremely faint.
raymo