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stanlite
27-08-2010, 01:19 AM
Hi all did this on the quick tonight (before clouds blew in) needs more darks (only got three before battery on cam died) 10min subs for 3 hours from a unmoded 1000D. Any hints you might have as always are welcomed.

http://i944.photobucket.com/albums/ad281/stanlite88/NGC6744.jpg

Tandum
27-08-2010, 01:24 AM
Grady, Look at each sub you have and knock out the bad ones manually. A number of the stars are triangles. Also how cropped is this?

Alchemy
27-08-2010, 07:04 AM
Tough one to start as your first galaxy, it's a lot better than my first one.
The galaxy has come up well, you're doing the right thing using lots of exposures.
Some things to generally look for in an image are
Focus across the image (stars are usually the way to tell), both in size, shape and also in the corners of the image.
Color balance, whether the sky is a grey, a little bluish tinge is quite acceptable, plus generally balanced. Saturation can be a personal taste, people do look at star colors, ie yellow and blue, and ifnyou are really fussy the distribution of the color across the star.
Lack of noise, usually in the background, more exposures helps, what's leftover can be selectively filtered or blurred.
Framing, just he balance of interest in an image... Personal taste at times.
Histogram, this will show all kinds of things, but you want to see no loss of data (clipping) and use the data to it's reasonably full extent, jet black skies generally not preferred.

Just a couple of things to check prior to completing an image.

For a first galaxy I it's a beauty, well done.

Garyh
27-08-2010, 08:00 AM
Yep you have choosen a pretty hard one for a first Gradly!
Lots of exposure is good, looks like some guiding issues or stacking issues?
Try the star rounder plugin for Photoshop. Works a treat but better if can avoid it. Background looks rather blue biased this end. So some levels/curves or color balance required.
Other than that a very good first go at a toughy!
cheers

stanlite
27-08-2010, 10:28 AM
yes i realise its a rather faint one to start with however at the location my scope can be set up in it is probably the best of the available choices till later in the month. the image is fairly croped as i still have yet to get a coma corrector and didn't want all the coma from the far edges in the shot. I will have to go through my subs this morning to get rid of sub optimal ones and try again. Also the stacking issue people might be seeing could be from a meridian shift i had to do so i might lose those 3 subs. Also Garyh is star rounder plugin a deconvoluion tool because if it is i would be very interested as i haven't yet figured out how to deconvoluted in photoshop yet lol.

renormalised
27-08-2010, 10:41 AM
Galaxy has turned out quite nice...good job for a first:)

mswhin63
27-08-2010, 12:00 PM
Brilliant first image, challending shot, gonna be tough for me to do my first one, whenever that happens.

Garyh
27-08-2010, 12:44 PM
Star rounder doesn`t do deconvolution but it`s great for enlongated stars. You can shift in x and y co-ordinates and vary the amount till you have fairly round stars..Down side is noise and some details might get stretched a little....
I think you can get a plugin deconvolution filter for PS?
Someone might chip in?
cheers

multiweb
27-08-2010, 12:49 PM
It's not bad at all at that FL. Quite an achievement actually.

stanlite
28-08-2010, 09:46 PM
added an extra hour of subs tonight and (discovered i had to) set the white balance for my camera i think the results speak for itself. Still some issues with pinched optics i need to resolve (pun intended haha). This image is not croped as much as the first.

http://i944.photobucket.com/albums/ad281/stanlite88/NGC6744whitebalanced.jpg

stanlite
08-09-2010, 01:06 AM
ok so have played around with my data a bit more since my last post here. worked out a few issues with the optics discovered more ect ect. This image has a total of 5 hours of subs (3 more then the last one). taken on a 8'inch newt. Final for a while (till i shorten tube more to put Coma corrector on for prime focus). Added alot of masks, filters and various others to this image (still have guideing errors or collimation problems but you get that). as always you comments are welcomed as they have helped me tremedously in improving my results. :D

http://i944.photobucket.com/albums/ad281/stanlite88/NGC6744fin4hours.jpg

Cheers Grady