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Mercury, Orion Nebulae, Oyster Nebula

Posted: 31 January 2021

The cloudy skies period that began on Monday, 18 January 2021, continued until Saturday, 30 January. Had 0.37" rain late Friday, 29 January.

Saturday morning I did some more tests with my new Tamron 150-600mm G2 lens on my Nikon D850 DSLR. This is Kitt Peak National Observatory from my driveway, 65 miles from the mountain. The photo (f/14, 1/800sec, ISO 400, FL 600mm) is cropped. Many of the observatories are visible.


Open: Saturday, 30 January 2021, 1746 MST
Temperature: 64°F
Session: 1589
Conditions: Mostly clear

12" f/8 LX600 w/StarLock
2" 24mm UWA eyepiece
2" 9mm 100° eyepiece
2" 2X Powermate
2" UHC filter


Upon arrival at the observatory I did some measurements for a possible new cabinet to be installed in the observatory.

1755 MST: sunset.

SYNCed observatory clock.

1757 MST: LX600 ON, StarLock OFF, High Precision OFF.

1816 MST: viewed the planet Mercury, 102X and 271X. A thin crescent phase was visible.

1821 MST: I moved to higher ground to photograph the western sky using the new Tamron 150-600mm lens.

1831 MST: some crepuscular rays were visible (focal length 150mm).


1847 MST: Mercury over distant mountains (focal length 260mm).


From the observatory patio I took these photos of nebulae in Orion. The exposures were short and untracked.

f/5, 5 seconds, ISO 25600, FL 150mm
Mouseover or tap on image
Mouseover or tap on image for labels

f/6, 5 seconds, ISO 25600, FL 340mm

f/6.3, 2 seconds, ISO 25600, FL 600mm

1905 MST: back inside the observatory. Viewed NGC1501 (Oyster Nebula), 102X.

1915 MST: High Precision ON.

Mounted the D850 DSLR at prime focus + 2X Powermate + 2" UHC filter, focused on the star Capella, and locked the 12" primary mirror.

Slewed to NGC1501.

1928 MST: StarLock ON.

Did some framing test images. Then did this StarLock autoguided, 5 minutes, ISO 6400, White Balance 4550K, image (slightly cropped) of NGC1501 (Oyster Nebula).


1950 MST: StarLock OFF, High Precision OFF.

Next, I tried to image Sirius B (the "Pup Star") at prime focus + 2X Powermate + 2" UHC filter, but was unsuccessful.

2008 MST: eastern sky brightening from rising waning gibbous Moon.

Viewed M42 (the Orion Nebula), 203X and 102X.

2029 MST: LX600 OFF.

Close: Saturday, 30 January 2021, 2038 MST
Temperature: 43°F
Session Length: 2h 52m
Conditions: Mostly clear

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