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I bought a new 3x Barlow lens and a 2x "shorty" barlow lens. I haven't done any stacking yet, but I tried the shorty and the 3x on Thursday night. It was cold and it was a work night, so I set up my telescope on my brightly-lit front porch (its a condo and you can't turn off the outside floodlights or porch lights). Polaris was through a tree, so I couldn't line the scope up to north and one of the alignment stars was behind my apartment so I didn't line up with it (in hindsight, I could have selected another star), so my alignment was terrible, so I didn't think I could keep Saturn centered with much more magnification. Even with all the light pollution and horrible alignment, the results were pretty good...
As it turns out, the 2x lens I had been using before is more like a 2.5x lens (calculated by counting pixels for Saturn on all 3 lenses), so I didn't get much more magnification out of the 3x than I had before. Next time, I'll stack them.
Attached is the result of the effort. Its a composite of Saturn at .4sec exposure (150 stacked frames) and the moons at 5sec exposure (50 stacked frames). Counter-clockwise from left is Dione, Titan (of course), an 11th magnitude star, and Rhea.
A 5s shot of the moons makes Saturn so overexposed that its tough to do the composite. I had to paint-out the halo. The raw (gamma slightly increased) 5sec shot is also attached. Enceladus and Tethys (why couldn't they be easier to spell? "Io"?) are just visible at 11:00 and 12:00 above Saturn. I couldn't isolate them for the composite. One of these days, I'll get up to the Poconos with my scope and maybe the clearer, darker skies will get rid of that halo.
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