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Thin Venus Crescent, Blue Sky Moon

Posted: 30 May 2012

Opened the observatory Tuesday, 29 May 2012, at 1803 MST, 102°F. The sky was clear but there was an occasional strong breeze. Began viewing Venus in the 8" LX200-ACF at 1808 MST, 77X. I then began setting up for prime focus imaging of Venus using the D7000 DSLR. I did a series of still and HD video recordings through a #21 Orange filter (to reduce the effects of atmospheric distortion). I found focusing difficult due to the atmospheric blurring of the thin crescent, so I slewed the telescope to the moon and used it as a focus target. With the focus locked, I slewed back to Venus and did more HD video recordings. The results were much improved. Using Keith's Image Stacker, I stacked 585 frames from a HD video recording, 1/800sec, ISO 1600, prime focus + 2X Barlow Lens. The color from the Orange filter has been removed from the resulting image:


I completed Venus imaging at 1837 MST. Viewed Venus through the Orange filter at 206X. I added a moon filter to the Orange filter; that provided a much cleaner view of the thin crescent phase.

At 1844 MST, slewed to the moon and did some observing at 77X. I then did a tour over the moon at 206X. Following that, I switched to the visual back and mounted the D7000 DSLR at prime focus for this 1/800sec, ISO 500 image, taken about 30 minutes before sunset:


Closed the observatory at 1907 MST, 84°F. A short but good session in the observatory.

Southern Stars, developer of SkySafari, has announced a nice new contest for the Transit of Venus. Get SkySafari (iOS or Android), photograph the transit with your mobile device (iOS or Android), and email Southern Stars your image. You might just win a new iPod touch, Android tablet, or iPad. Check it out at:

Comments are welcome; use the Comments section below, or you can Email Me. Thanks.

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