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View Full Version here: : OK Troy - reluctantly (smile) - M45 Sat Night Leyburn


Bolts_Tweed
23-11-2009, 10:34 PM
;)

Here it is warts and all. I've just done a colour adjustment to correct the modded 350D colour.

As I said there isnt eniough useable data with all that smoke and a heap of noise needs to go before I wrap it up, star colours need adjusting (there are some little red ones in there), I havent even cropped the Televue vignetting - Ive got to get a wide field corrector.

I was trying to go really deep to get some of the surrounding faint dust but its beyond a 4inch scope i think. This is embedded in a mile of dust - see Rogelio Andreos image

http://blog.deepskycolors.com/archive/2009/10/20/deep-Field-From-California-to-the-Plei.html

And while Im at it check out his Witch Head

http://blog.deepskycolors.com/archive/2009/11/16/witch-Head-Nebula-and-Rigel.html

But alas not with 350D even modded - maybe when the ST8300 becomes avialable (note he is only using a 4 inch scope for these - Tak FSQ)

This is virtually raw data - I know its noisy etc, the gradient annoys me etc etc etc but im off to the US for December so I cant add to it until the new year and I thought after our conversation on the weekend i'd (reluctantly) share what I wasted most of a weekend on :)

Televue np101is, Modded 350D, DSS, levels and colour in PS so far. 8 x 20 min subs with icnr on

Mark Bolton

dpastern
23-11-2009, 11:38 PM
Doesn't look too noisy to me and I can't even spot the gradient. Nice one! How did Troy go?

Dave

troypiggo
24-11-2009, 05:39 AM
Aah, Mark - now that's the sort of dust detail I wanted. Shows what 4 or 5 times the data can do. Wonderful. I see what you mean about the brighter stars, but hey - the nebulosity more than makes up for it.

20 min subs - your camera cooled, or just filter modded? Was talking to someone else Saturday night (Ron?) who said he does subs that long, 15 mins, up to 30 mins, with an uncooled DSLR. I've been told, or rather recommended strongly, to keep subs down to 5 mins or so. Wondering about noise at those sort of exposures, and whether darks work just as effectively. I mean, I guess they have to, but there must be just so much more noise to get rid of. And the stars saturate so much more?

iceman
24-11-2009, 05:53 AM
Great image, that's really nice!

Bolts_Tweed
24-11-2009, 09:31 AM
Thx David Troy and Mike


David - yeah mate to the lower right of the Merope section particularly - just that faint colour noise - I like em a lot smoother than this and it doent matter what I image without the corrector they all look like this dark corner and bright centre - will fix it.

Troy - not colled mate just modded. Yeah I've been pushing it exposure wise lately - I found myself taking the same images year after year for 20 years or so and decided to experiment a bit to try a different view on some old favourites. Obviously s/n ratio is the principal problem but generally that just means more exposures and thus more time (8x20+icnr = 5 hr 20 and add in the 3 i dicarded its 7 hr 20). I have found incr does a far better job on a 350D with all the amp glow but others out there are having some success with master darks on later models. Apart from exposures it just a factor of tracking (mount performance and alignment) and optics standing up to it. This has no flats which would fix those corners - i'll wait until I have enough data to do that. Just experimebnting thats all - I think Robeirio goes a bit far with his streching some times but I like his stuff cause it shows what is there apart from the DSO - I use it as a road map. His image encouraged me to chase the faint dust under the horsehead a few months ago.

It was Ray the Garden Gnome you were talking to - he rang last night.

Any way - thx - i've got to go and pretend i'm smart for another day at uni

Catch Ya

Mark

Bolts_Tweed
24-11-2009, 09:35 AM
Sry - I forgot - stars - yep thats the problem with long exposures - cant do much about the 7 sisters - theyre in dust and will bloat - its just a matter of extent - I have pinched them before and it is ok but if you are used to pinching it stands out like well - you know what.

The others are easy fixed with a shorter duration layer mask with sky colour matched will fix em then another with the saturation levels adjusted will give something approaching original colour

M

Paul Haese
24-11-2009, 07:56 PM
Nice image, good colour but the brighter stars could do with some reduction.