The benefits of stacking. [ for newbies].

[Camelopardalis (Dunk)]

M42 can be a tricky one as raymo says, but I'd say give it a go... from a capturing point of view, it presents a challenge as it's very bright and quite large, and there's the huge dynamic range raymo mentioned between the core, where all those lovely trapezium stars are buzzing away, like kids on sugar drinks which makes it really really bright. Then you've got the colourful bowl and then the outer reaches of the sail and beyond.

If you have a look at my attempt http://www.iceinspace.com.au/forum/s...d.php?t=128452 you'll see I've taken multiple sets of exposures, mostly 2 minutes but then some much shorter ones to represent the core...which was composited with the rest during processing.

I used the same ISO, which probably wasn't very smart...but try changing your camera settings and exposure lengths and see how it comes out.

The Tarantula nebula in the LMC is also a tricky one, I intend to use a similar tactic as M42 for that one...

[CJ (Chris)]

Thanks fellers. I'll give them a go some day. Don't hold your breath.......

[griz11 (Dan)]

I too am new to AP and received the same advice to do many more subs than I was doing. I was trying 5 or 6 at long exposure lengths and the results were very noisy and grainy. Decided to do 20 the other night. But when I had 5 on my disk I stacked them looked it over then waited for the next image and did it all over. After 8 images it really started looking good. I was amazed at the end result. And I'm convinced that getting many more subs than you think you are going to need is a good policy. Initially I was trying to get 2 to 3 targets each session. Now I've cut back to spending the whole night on just one target and getting as many images as I can. It took me awhile to get the hang of DSS. But once you do get it figured out it works very well.

Griz

[LightningNZ (Cam)]

Originally Posted by raymo

Thanks Cam; I'm intrigued, why would you lurk?
raymo

Heya Raymo

Just got lots going on lately - brought work home for a couple of weeks, and also getting back into recreational computer programming - and haven't had the decent weather, time or inclination to take my own shots.

Just found a site today while on a Sunday drive with my wife, which might be a good spot for doing astrophotography. I'll probably be active again during the Xmas holidays when I have a bit more time for myself.

I'm actually contemplating selling my Astrotech AT65-EDQ now that I've got the 6" F/5 Newt. Will see how things go over summer.

So yeah, with not having much to contribute, or much spare time I've only been poking my nose in from time to time.

Cheers,
Cam

[raymo]

Fair enough.
raymo

[Regulus (Trevor)]

A very helpful post Raymo, thanks - Trev

[raymo]

Glad to help Trevor.
Lots of subs is good Dan, but eventually you do reach a situation
of diminishing returns. 50 is better than 20, and 100 is better than 50,
but over a hundred the improvement seems to be less noticeable.
raymo