Comments on: M101, The Pinwheel Galaxy

By: Louis

Louis — Wed, 26 Mar 2025 10:19:40 +0000

Ron, excellent image. Thanks for sharing the process flow you used.

By: Astrodoc

Astrodoc — Wed, 11 Jun 2014 14:19:48 +0000

In reply to Mark.

I haven’t tried exactly 10 hours, but I did compare the 41.33 and 27.33 hr versions. The difference in luminance is what drives the difference in result — 29 hr vs 15 hr. This really made a huge difference. However, when I considered whether to go for another 10 hours, I figured I’d only get about a 15% improvement in S/N, so I decided to press on for other objects. There are so many objects and so little time 🙂

I aim for an image scale around 1 arcsec/pixel, so f/6.8 works great for me with my camera, which has 9 micron pixels. Your image scale of 1.3”/pixel is very good. If you think it is under sampled for your seeing, consider using PixInsight’s new Drizzle combination process to improve resolution (and your image scale). You could also shoot unbind, which would give you around 0.65″/px – excellent if you often have good seeing.

By: Mark

Mark — Wed, 11 Jun 2014 06:37:22 +0000

Hi Ron,

Saw this great image on the ASA forum.

It would perhaps be instructive to process, say, 10 hours worth, and see what the difference is. I am currently also using ASA10N with all the focal ratio options, but the farthest I’ve gone at f/6.8 is 5 hours 20 min with X2 binning for a scale of 1.3″/px.

Regards,
Mark

By: michael

michael — Mon, 09 Jun 2014 21:37:04 +0000

What an amazing shot Ron!
When I first started observing with an SC-8 this galaxy was my nemesis. I had no idea what to look for…just that the guide books said it had high luminosity. Night after night I searched the appropriate sky, often using high magnification. You know what I was doing…looking right through it. …Looking at the leaves and missing the forest!
Colours and details are wonderful. Keep up the great work.

By: Astrodoc

Astrodoc — Wed, 28 May 2014 00:33:59 +0000

In reply to Roy T. Conrad. Thanks! Yes, my images are for sale. I need to finish it first though! ;-). I will let you know when it is ready. Clear skies!

By: Roy T. Conrad

Roy T. Conrad — Wed, 28 May 2014 00:30:08 +0000

Ron, that is one of the most beautiful picture that we have ever seen. FANTASTIC. If you make prints I would like to purchase one.

PS.
I have showed it to a few people and they loved it.

Roy and Paula.

By: ken

ken — Fri, 09 May 2014 15:36:09 +0000

Very nice