nikonshooter Loc: Spartanburg, South Carolina

This afternoon I got around to processing the M31 project from 12-8-15.

Once again, 200 - 30 second exposures at 1600 ISO - Atlas Pro mount - Nikon D800e with 200x400 F/4 lens at 400mm. I did not guide. Polar alignment with "Alignmaster" software. Imaging software Backyard EOS for Nikon. Supporting files, 50 flats taken the morning of Dec 9th, 50 Bias, 50 darks. No pause between photos. Focusing with a Bahtinov mask.

Post Processing: Deep Sky Stacker for Registering, Calibrating, and Debayering. PixInsight for Backgound Extraction, Color Calibration, Linear Stretch, RGB Curves Adjustment, Saturation Curves Adjustment, Luminosity curves adjustment - Save at 16 bit Tif file and off to Photoshop CC, Luminosity masking for selective tonal, color, and structure adjustment. Star removal - layer mask.

I know I am forgetting something - if you see something curious or missing, let me know.

I am just having some early evening fun shooting short exposures!

M31 12-8-15

(Download)

astroturf Loc: vacaville ca.

very nice good work :thumbup: :thumbup: :thumbup:

CraigFair Loc: Santa Maria, CA.

Very, very beautiful Coach.
Craig

Albuqshutterbug Loc: Albuquerque NM

How early in the evening? I'm wondering how straight up you're shooting.
Nice job any way you look at it.
;)

nikonshooter Loc: Spartanburg, South Carolina

I am done by 9:30 or so with subs. Avoid flipping. I like shooting straight up, better seeing .... 60 degrees plus!

nikonshooter Loc: Spartanburg, South Carolina

Thanks to all for the compliments. I too am learning.

Albuqshutterbug Loc: Albuquerque NM

I just looked up your elevation.
At 600' you have more air to breath than I do but you also have a lot more air to shoot through. I am 4500' higher than you are so that should help when I get this stacking stuff figured out. It certainly helps my single shots.
I also try to shoot as straight up as I can just to eliminate the air factor as much as possible.
I have an additional 5000' pile of dirt to the East of me called the Sandia mountains. Part of the Rocky Mountain chain, there are plenty of places to pull out on the way to the top at 10,378. There is a double parking lot at the top but it is pretty will lit with nasty street lights.
One of these days when it warms back up I am going to have some fun along the road to the top. Right now it is just too dang cold up there to be fun. Heck its pretty cold here.
Keep on sharing and giving us ideas, they all help.
Thank you!
Jim

Albuqshutterbug Loc: Albuquerque NM

One more question. ( For now anyway..)
What was your aperture?
I think my f2.8 was too open. I may need to close down a bit to get better definition.

nikonshooter Loc: Spartanburg, South Carolina

My recent images were shot at F/4 as this was fixed on the Nikon 200/400. I also use a F/2.8 70x200 lens.

My scopes are F/6.7 - Vixen, and F/10 Celestron SCT.

Every lens has a sweet spot regarding aperture. When shooting night images - one would think that shooting wide open (increase light gathering - allow for shorter exposures and/or lower ISO's and therefore lower luminosity and thermal noise) is the ticket - finding the lens sweet spot is sometimes more valuable...depending on the lens. I would google: What is the sweet spot for (enter your lens info) to see if anything comes up. If not, try "shooting down - daytime" starting with F/2.8, then stop down 1/3 of a stop (one click on your DLSR) and take successive images and continue at one click (your aperture wheel) at a time. Compare your images.

Usually a F/2.8 lens will perform better in the F/5.6 to F/11 range.

If you know in advance that you will be cropping 100 percent or more....shoot at F/2.8 and don't look back. But if shooting "tight" it's best to find the "sweet spot" as the aberrations will be found at the edges.