On Monday, June 5, 2017 at 9:05:45 AM UTC-7, Razzmatazz wrote:
On Saturday, June 3, 2017 at 8:06:09 PM UTC-5, palsing wrote:
On Saturday, June 3, 2017 at 3:39:05 PM UTC-7, Razzmatazz wrote:
Bad weather is finally over, and the skies have cleared here in the Midwest.

This large galaxy, M101, has a huge brightness range, which makes it a challenge to process. I once saw a Palomar glass plate of this object which showed the huge range quite well, because negative film has a non-linear response at the very bright end.

I posted this shot that I did last night as a negative. It shows the very faint extensions better than a normal image. It also brings back memories of the old film days before CCDs. Note the numerous tiny background galaxies.

https://www.astromart.com/common/ima...8.jpg&caption=

AP 17" F8 Astrograph
STL11K camera
40 x 5 minute Luminance
AP1600 mount

Razzy

Very nice!

At the eyepiece of my 25" F/5 I like to try and identify as many of the individual NGC's and other designations associated with M 101, as shown on this labeled photo (drawing?)...

http://www.deepskyforum.com/attachme...0&d=1432064109

... it is quite a challenge to get more than about 6 or 8 of these stinkers visually... but that is what the visual aspect of the hobby is all about, IMHO.

I spent a lot of eyepiece time on this guy from about 9200 ft. on the slope of Mauna Kea last month, it was an amazing sub-arcsecond night, I had a 22" f/4.5 at my disposal...

Paul A

Mauna Kea is a great place from which to observe. It is incredibly dark at the 9200 ft. visitor center, especially after the tourists leave and all the lights are turned off. A 22" is just the ticket for deep sky observing up there.

Were you able to see any of the very faint background galaxies around M101?

Razzy

Well, we weren't at the Visitor Center itself, but rather we were a couple of hundred yards up a forest service road west of the Visitor Center, where the all-night lights of the VC were not much of a problem.

Yes, I had that labeled chart printed out and was able to identify most of the NGC objects shown thereon, as did many of the other 8 or so observers in attendance. It was a glorious night...

\Paul A