Friday, May 04, 2007

observing and sketching (Blue Mountain)

Happily, Friday night, shortly after arriving at the E.C. Carr Astronomical Observatory off Georgian Bay, I got a bit of observing in. Even though I had to scramble a little to get set up...

I wandered into the roll-off roof observatory. Dietmar and Charles were aligning the 14" Celestron catadioptric 'scope. Just in time to view Saturn through the big 2" eyepieces. It was beautiful. I could see many moons. Possibly 6 or 7.

Later, I looked at Saturn through Ian's massive, beautiful, home-made dob (the mirror alone weighs 60 pounds) at 250x. I could see more moons, more details in the rings, colours like pink, white, and tan, on the planet surface. An incredible view.

With my 8 inch on the CAO Observing Pad, I took in the Beehive (Messier 44 or M44) in Cancer. It was easily visible with the naked eye. With my 26mm eyepiece, at 77x, it was way too tight. I asked, of the crowd there, if there was a wide-field eyepiece (with 1-1/4" shaft) that I could borrow. Ian offered up his Tele Vue 40mm Plössl (with 43° AFOV) which helped me back up a bit. But even 50x was too much. I think I can go down to 29 power with the SP-C8. I'll have to try the Beehive again at that level...

It is such a cool thing trying other eyepieces. Helps get a sense of the power, field, eye relief, etc. I found the eye relief (or the exit pupil) on the TV 40... well, awkward. I was a little surprised about that. The Tele Vue web site says the eye relief is 28mm.

Dave G.—charging through the Messier list with his Dob—remarked that he was having a tough time with Messier 67. He knew approximately where it was but had not seen it. I used this as cue to pull my Tirion charts and fire up light box 2.0. And before I knew it, after starhopping, I had found it! I sketched M67 quickly (through the TV 40mm Plössl) to verify if I was on target.

My sketch on 4 May 2007 at 10:50pm. Cleaned, rotated, laterally-inverted, and colour-inverted in Fireworks.
Photo by Jan Wisniewski from the SEDS web site.

I wanted to view more galaxies from this dark site so I asked if M81 and M82 in (or near) Ursa Major might be good targets. I was encouraged to go for them. Once again I starhopped through the area and found both galaxies. It was fantastic! In Ian's 40mm eyepiece I was able to see both Messier objects in the same field. That was very cool.

At 11:26pm I sketched Messier 82 (M82). I thought I could see some texture, some granularity, particularly around the centre regions. Others said it was possible. On examining photographs of The Cigar Galaxy, there are a number of dark patches through the middle of the galaxy. Wild.



When the moon came out, while pleasingly close to the horizon and distant clouds, it washed out the sky. It was dramatic. Most of us packed it in.

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I had rewired my red LED light box earlier in the week. Now I have 2 push-button on/off switches, one controlling each half of the light box. This will allow me to use it for 8½ x 11 sheets without blinding myself. My first outdoor run with 2.0 was this weekend. It worked well.

There is a notable change in brightness when one half is shut off. I was surprised by that...

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It occurred to me this evening that I have "arrived," in terms of starhopping. When I first heard about this technique, I thought it sounded very difficult. My first attempts were not optimistic. But I can tell I'm getting better at it. It is a combination of things, of course: my "ring" or scale transparency sheet, the wonderful Tirion charts, my new light box, getting used to the viewfinder's rotated view and the telescope's reversed view, and various circuits in my brain getting activated. It's increasingly satisfying. It's all starting to pay off.

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