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NGC2336 Galaxy, M1 Crab Nebula

Posted: 28 February 2014

Opened: Thursday, 27 February 2014, 1932 MST
Temperature: 64°F
Session: 658
Conditions: Mostly clear, clouds low S-W-N

February has been a tough month for observing due to frequent cloudy nights. Lost some nice ISS passes, including one ISS-Sun transit, due to cloudy skies. Thursday, 27 February 2014, it was cloudy and windy all day until after sunset. Then the sky mostly cleared up and the winds went away. More clouds, and even rain, are in the forecast for the next few nights so I was happy to get the chance to be back in the observatory.

As I walked out to the observatory, the Zodiacal Light was very visible, running all the way from the western horizon up to almost the zenith. At 1939 MST, viewed Jupiter through the 8" LX200-ACF at 83X. Three moons were visible. Then slewed to M42, the Great Nebula in Orion, and viewed it at 83X. Added the 2" O-III filter; the view of M42 was not as good as without the filter. Too much of the nebula was hidden by the dimming from the filter.

1945 MST: slewed to M82 galaxy to check on supernova SN2014j. It has faded even more from its peak magnitude last month.

Slewed to NGC2336 (galaxy) and began preparations for prime focus imaging using the D7000 DSLR. Unlike previous imaging of NGC2336, I did not use the off-axis guider this night. Mounted the camera at prime focus using the 1.25" visual back. Did a focus test on the star Regulus using the Bahtinov Mask. Did a framing test exposure of NGC2336, 2 minutes 30 seconds, ISO 6400, unguided. Framing was OK so did 23 more unguided exposures of 2 minutes 30 seconds each (for a total of 60 minutes of exposure time). Twice during imaging, the neighbor to the north turned on his bright, horizontally aimed, unshielded floodlights. Since NGC2336 is a circumpolar DSO, I was worried that the bright floodlights would impact my imaging, so I set up my "Light Shield". (For more information on my "Light Shield", see my article "Simple POD Light Shield".)

During post-processing, I stacked the 24 exposures using Lynkeos software with this result:


Seeing must have not been very good this night as the one hour exposure is slightly less detailed than the previously done 30 minute exposure.

2114 MST: completed imaging of NGC2336. There were still some clouds low in the southwest and west.

Slewed to M1 (Crab Nebula) and began a series of 1 minute, ISO 6400, unguided exposures. Did one framing test exposure; adjusted framing and did 15 unguided 1 minute, ISO 6400, exposures. Unfortunately, 10 of the exposures had some slight trailing. This is a stack of 5 exposures (effective exposure length of 5 minutes):


2150 MST: completed imaging of M1. Clouds in the southwest were getting higher in the sky. I monitored the clouds for a few minutes, eventually deciding that they were moving too fast towards me and would likely not allow time to set up for additional DSO imaging. I began closing up for the night.

Closed: Thursday, 27 February 2014, 2213 MST
Temperature: 53°F

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