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More Spectroscopy & Some Lunar Imaging

Posted: 13 October 2011

The observatory was opened at 1814 MST, 83°F, to clear skies. First, I did a complete AutoStar alignment reset using this technique from the AutoStar expert, Dick Seymour:

The quick "fix" is to tell the Autostar you're Alt/Az mounted, turn it off, turn it on, "fake" a One Star Alt/Az align (which will clear the bad data), PARK. Turn off, turn on, set back to Polar, turn off.

With moonless nights upcoming, I decided I wanted the best possible GOTOs and tracking, so I did the procedure. I finished the realignment at 1840 MST.

By 1850 MST, the moon, one day past Full, had risen above the hill to the east. I began setting up for some more D7000 DSLR spectroscopy using the Star Analyser. Here is a 1/25sec, ISO 1600, image:

Deneb - Spectral Type A2

I ended imaging. At 1919 MST, viewed the moon, still low in the eastern sky, at 77X. A little more terminator was visible this night. By 1937 MST, Jupiter had risen above the hill, but was too low for good viewing. Three moons were visible. At 1945 MST, I returned to the moon and did some lunar limb observing. There were some good views of peaks and valleys along the illuminated portion of the limb. At 2008 MST, the moon was high enough for better seeing and I began setting up for lunar imaging with the D7000. I swapped the diagonal for the visual back and attached the camera. The entire lunar disk was not visible in the viewfinder. I added the focal reducer and was able to capture the entire disk. This is a 1/500sec, ISO 100, exposure, at prime focus + focal reducer:


I removed the focal reducer and added the 3X TeleXtender and did some imaging along the lunar limb. This cropped image, 1/320sec, ISO 500, shows some of the peaks and valleys that were visible along the limb:


Here are three views along the terminator, 1/320sec, 1/320sec, and 1/250sec, representatively, ISO 500:




I ended imaging and swapped back to the diagonal. At 2040 MST, viewed Jupiter at 77X. Although it was somewhat higher in the sky, seeing had not improved. Decided to end the session as I planned a busy next day, doing computer and iPhone OS updates.

The observatory was closed at 2055 MST, 70°F.


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