Log in

View Full Version here: : ngc253


allan gould
04-07-2009, 05:17 PM
Last night I thought I would try to cure a few issues with my guiding (eventually did so, but thats another story) and in between the gusts of wind we have been having here in Brisbane along with 80% full moon, I thought that I would have a go at NGC253. I was on able to get 23 x 1 min shots which were not wind affected and thus gave a somewhat poor stack for the image. I was surprised that compared to the attached Hubble shot I was able to get hints of the dark gas streaming out of this galaxy. I'll have to go longer, deeper and sharper with the DSI to do this galaxy justice but its given me encouragement. Sorry about the Jpeg artifacts but thats life too.

Paul Haese
04-07-2009, 05:30 PM
Looks good so far Allan. Stars are nice and round.

allan gould
04-07-2009, 06:12 PM
Thanks Paul, sorted the guiding - so apart from wind gusts as I was in the open, I was pleased with the guiding. But I think I'll have to get to a dark site, use the longer focal length of my 10" to do a mosaic of this galaxy, and get the detail I'm after. But Im convinced it's do-able and then i"ll be sattisfied. Think each frame will have to be 1-2 hours at the minimum for the mosaic to get it smooth enough to do something worthwhile.

multiweb
04-07-2009, 07:49 PM
Under moon glow and in the wind? Are you serious? :windy:
That is just a superb result. :thumbsup: Rock solid tracking and excellent focus. You're on your way for a great shot when this moon goes away.

Hagar
04-07-2009, 11:12 PM
Looks like you have your guiding problem sorted Allan. Nice image.

peter_4059
04-07-2009, 11:38 PM
You can see some detail starting to build in this Allan. Give it a few more subs and you'll notice a real difference in how smooth the image becomes. We just need a few good nights without this wind!

renormalised
05-07-2009, 12:18 AM
Nice detail in the shot there, Allan. If you want to reduce those jpeg artifacts, change the compression ratio on the images when you save them. Might mean you have larger images to deal with, but you'll have less compression artifacts.

allan gould
06-07-2009, 02:54 PM
Had a go at reprocessing the 23x1min DSI II shots that I had submitted but used photoshop to remove a flat field image that I had mastered at the same time (in preparation to building a light box). The use of a flat field certainly enhances the shot and makes fainter stars visible in the image.
Peter, you'll have to help me with some more soldering

jase
06-07-2009, 03:09 PM
The repro is looking great Allan. Pleasing details on display. Good job :thumbsup:

Peter Ward
06-07-2009, 04:00 PM
Humm...Might want to make a small correction....the attached "Hubble Shot" wasn't taken by the Hubble...I think it's Jay Gabany's image using an RCOS/STL11k combo ;)

allan gould
06-07-2009, 04:07 PM
I stand corrected. The image was at http://apod.nasa.gov/apod/ap060421.html and I didn't read it closely enough, my apologies to R. Jay GaBany. Still its the image that I'm aiming to get close to because of the beautiful detail and fine structure revealed. Most shots burn it out completely leaving the large dusty lanes evident. But I was pleased to get what I did with an old Celestron 8" orange tube scope on a moonlight windy night with a $500 camera.
Thanks for pointing it out Peter