Comet Lulin

[Fay]

This was taken with the Canon, ED80, cls filter, 17x120secs.
I am not too happy with this. I stacked it in DSS, which has a comet aligning facility, but it does not work too well, you get fuzzy trails on the stars, where the program has tried to freeze their position. I layered in PS but there is a lot of trailing to process out & I decided, it makes a dishonest image when too much has to be done.

[Carole]

Well done Fay

Carole

[RobertM]

Very nice image Fay.  How did you keep the comet still ?

[Fay]

Well the nucleus was a bit elongated with movement. I stacked with DSS concentrating on the comet, & then  layered it with the original image.
Stacking in DSS, was supposed to freeze the stars but what it does is make a lot of dull trails below the stars, it is not a very good option. I did then stack, on the comet nucleus,  in Astroart, but the result was a very low luminance comet with stars that were streaked.

With a Maxim stack, the computer nearly ran out of memory & it was very slow & had to be aborted.

DSLR images are a lot different to ccd images, to do.   

[JohnP]

Robert - DSS has a comet stack feature which does a two part stack.. It stacks on stars & then comet nucleus & then overlays... However, It's got problems & leaves streaks (you can see these in Fay's images)

John

[RobertM]

Hi John,  Yes I tried to use DSS, the result was far from what I was expecting i.e. rubbish.  Can't complain thought as it is free...