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TrevorW
29-11-2008, 09:04 PM
This is another stack I did last night although I'm not overly impressed with it no matter how hard I tried couldn't get more of the nebulosity around the stars to show definitely need longer exposures on this one.

Theres 22 minutes exposure in here best 38 by 35s images stacked in DSS


Cheers

Peter Ward
29-11-2008, 11:23 PM
Trev....you have hit upon what many novice astro-imagers often neglect.

Short subs, in the main don't cut it.

I could chant my mantra, suffice to say, for dim objects try *much* longer sub exposures. (at least five minutes). You need to capture signal quicker than you are capturing noise.

Focus is also very important, and is easy enough to nail with a critical eye.

Stick with it.

AlexN
29-11-2008, 11:56 PM
I have to agree with Peter. Even without guiding, just a good polar alignment, you should be able to stretch to 3~4 minute subs. I have managed 270sec unguided subs at 714mm focal length with the EQ6 Pro..

Focus is perhaps one of the only things you can always get 100% perfect, provided you take some time and be very critical.. Take your time with focus.. Its better to use up an hour getting focus spot on, than waste an hour taking out of focus subs.

Do your best to get the mount polar aligned well, drift aligning is easy once you get the hang of it. I used to use a 2x barlow + 12mm reticule to drift align, as you see the drift quicker under the higher magnification... If you can get 10mins in the reticule ep without drift, you could easily take 4 minute subs, which will increase your image quality heaps.

Keep at it! :)

Bassnut
30-11-2008, 12:35 AM
Ahh Trevor, your a smart man, so you deserve a thrashing on this one, its not good really :D. I get the feeling once you get the hang of it youll be off running. Hang in there ;).