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Solar Transit Behind Kitt Peak National Observatory From Mount Lemmon Highway

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My wife Susan and I, along with a dozen or more other sunset buffs, have developed an annual tradition.  At the winter solstice the sun passes behind the observatories of Kitt Peak National Observatory as seen from about sixty miles away on the Mount Lemmon Highway.  For about three days before and after the solstice, one can get some great imagery of the sunset highlighting the vast array of 20+ scopes.  So, in accordance with my wife's and my tradition of Christmas Eve memory making, we were up on the Mount Lemmon Highway with about ten other folks. 

I completed my attempt to learn to videograph the event in H-Alpha using a Mallincam Junior PRO camera and a Lunt 60mm THa/B600.  It did not do badly, but I'm about done toying in that bandwidth and will go back to white light with the 90mm refractor.

Good Points:
1.  Alan Strauss reminded me what I learned last week when I lost the luminance channel on the S-Video feed due to a connector failure.  The sun photographs better in H-Alpha monochrome where more surface details come out.  So, since I can't turn that channel off in the S-Video feed, instead I cut the saturation down to below 10%.  Some color is available, but not the usual red poker chip.  MUCH better detail available.
2.  Last week I used full record and ended up with a 7000 frame 4 GByte AVI file.  At Dean Ketelsen's suggestion, I used manual snapshots during the run on the control software for the Mallincam so instead of a continuous 30Hz AVI video, I ended up with several hundred PNG pics that easily converted to a movie file using Microsoft Movie Maker.  And only about 8 Megabytes.
So, much appreciation to Dean and Alan for forcing me to do things the right way.  Plus, my wife Susan and I practiced sunsets a couple of nights at the Saguaro West Visitor Center near home, with her using a Canon EOS Rebel T3i.  Baby steps and practice seems to help!
Bad Points
Everything seemed ready to rock and roll early on, but of course that can't be allowed to happen.
1.  Since I was in H-Alpha, I have no way to align the camera output with the horizon.  So clever me, I turned off tracking on the mount and saw where the motion of the image was going, and rotated the camera.  But idiot me did it so it was moving vertically, NOT along the ecliptic.  So the video has the sun going straight down and KPNO at an angle.  Duh.  Another lesson learned.
2.  For efficient operation I had the monitor I use for focus set a foot away from the scope, and the laptop for recording about three feet away.  Both use 30 foot data, power, and control cables provided by Mallincam.  All during prep time, the digitizer was back to working in S-Video.  About 10 seconds before solar contact, the S-Video somehow pulled out of the digitizer.  Note the start already has some detail, then a quick jump when I was verifying the connection instead of manually triggering the snapshots.  With the last second fuss, I forgot to turn off the mount tracking so the video follows the sun, not fixed on Kitt Peak.  ANOTHER lesson learned.  If I do this again next year, I will use a dual saddle with the 90mm refractor (and my other Mallincam Junior, computer, and digitizer) and align the two fields of view on solar surface detail, then bring the two down to the horizon freeze point.
I thought I was having a bit of trouble with both varying transparency as well as seeing; Jim Miller next to me never could get his LS60/B1200 to focus so there was some less than desirable conditions all around.  I got a little of the wisps of cloud coming out of the valley beside KPNO and caused one sunspot to flicker.  So one spot is winking in and out.
Bottom line, lots of fun when it works, the people were great, and some great people have helped me through the learning curve.
Afterward, Jim and Elaine Miller and my wife Susan and I stopped at Village Inn for dinner, and found out that Jim and I are both retired Air Force, with a bit of overlap but really unique experiences.  Nice conversation all through dinner.
All in all, the pure visible light is loads easier to do, so I'm not sure how much value is in the H-Alpha, but the surface detail was very striking, more pronounced in the monitor view where I got luckier in balancing parameters.  Decisions for next year to make...

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