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Thin Crescent Moon, Venus, Mars, Mercury;
More Messier Galaxies Imaging

Posted: 20 April 2015

Open: Sunday, 19 April 2015, 1803 MST
Temperature: 90°F
Session: 812
Conditions: Mostly clear, some clouds West and North

1810 MST: Viewed Venus, 83X. It was a nice view of the almost half-phase planet against a bright blue sky 47 minutes before sunset. Then slewed to the Moon, but the thin crescent was not yet visible in the 8" LX200-ACF or the 7x50 finderscope. Some clouds in the western sky were not helping. 1830 MST: still no Moon. 1841 MST: Venus was naked eye visible. 1843 MST: crescent Moon sighted in the 7x50 finderscope, then at 83X in the telescope. This series of handheld iPhone 5s afocal photos, 83X, shows how difficult it was to initially see the thin crescent Moon in the eyepiece and then its changing appearance as the sky became darker:

1847 MST:

1849 MST:

1901 MST:

1920 MST:

The images were cropped from the full-frame photos.

This cropped D7200 DSLR sky photo shows the crescent Moon at 1910 MST:


This D7200 photo taken at 1916 MST shows Venus at the top and the Moon near the bottom. Mouseover or tap to see labels.

Mouseover or tap on image
Mouseover or tap on image

1924 MST: the Moon was now in a tree as seen from the observatory. 1928 MST: viewed Jupiter, 83X. Three moons were visible.

1930 MST: I stepped outside of the observatory and using my Celestron 12x70 binoculars I was able to view the Moon along with the planets Mars and Mercury low in the western sky. They were not close enough together to see in the same field-of-view however. This handheld D7200 photo taken at 1939 MST, f/5.6, 1/20sec, ISO 3200, FL 140mm, shows the Moon and planets (mouseover or tap for labels):

Mouseover or tap on image
Mouseover or tap on image

1941 MST: ended Moon, Mars, and Mercury imaging. Mercury was too low and clouds were interfering.

Began preparing for Messier Catalog galaxy imaging. Mounted the D7200 DSLR at prime focus + extension + off-axis guider. 2016 MST: focus test on the star Regulus using a Bahtinov Mask. Then began guided imaging. All images were initially processed in Aperture, then Neat Image (to reduce digital noise in the JPEG images), and finally GraphicConverter, and are cropped from the full-frame image.

M63 (Sunflower Galaxy), 10 minutes, ISO 5000:

M89, 5 minutes, ISO 5000:

M102, 5 minutes, ISO 5000:

M104 (Sombrero Galaxy), 5 minutes, ISO 5000:

M83, 10 minutes, ISO 6400:

My Messier Catalog Astrophotography Album is now complete. I may redo some of the D7200 DSLR images after the Raw converter is released, which should reduce the digital noise apparent in some images.

2236 MST: ended DSO imaging. 2244 MST: viewed M83 galaxy, 83X.

Close: Sunday, 19 April 2015, 2255 MST
Temperature: 63°F

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