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Zodiacal Light, Eskimo Nebula (SHO filters)

Posted: 14 February 2020

Thursday, 13 February 2020, dawned clear and the sky stayed clear.

Open: Thursday, 13 February 2020, 1806 MST
Temperature: 66°F
Session: 1437
Conditions: Clear

12" f/8 LX600 w/StarLock
2" 24mm UWA eyepiece
1.25" 15mm eyepiece
Atmospheric Dispersion Corrector
2" SHO filters


1811 MST: LX600 ON, StarLock OFF, High Precision OFF.

Viewed Venus, 102X. Switched to 163X + Atmospheric Dispersion Corrector. Focused and locked the 12" telescope primary mirror. Slewed to Mercury and viewed it. Unfortunately, it was just too low in the western sky for a good view.

Returned to Venus. Adjusted the AutoStar backlash RA and Dec percentages to 000% (I had previously set them 001%). Setting to no backlash performed much better as there was no delay in the start of slewing.

I had planned to image NGC7662 (Blue Snowball, planetary nebula) this night but as it turned out it would be too low in the northwestern sky after the end of Astronomical Twilight (1930 MST).

1840 MST: began preparing the D850 DSLR for imaging.

1900 MST: viewed NGC2392 (Eskimo Nebula), 102X.

1911 MST: the Zodiacal Light was visible.

1925 MST: set up the D850 DSLR with a 14mm UWA lens on a tripod outside of the observatory. I then had to wait several minutes for passing airliners to stop flying over and passing through the Zodiacal Light.

1948 MST: took this photo showing the Zodiacal Light, the Milky Way, Pleiades, and the Double Cluster, D850 DSLR (f/5, 30 seconds, ISO 5000, White 5560K, FL 14mm).

Mouseover or tap on image
Mouseover or tap on image for labels

1950 MST: returned to the observatory. Mounted the D850 DSLR at prime focus + 2X Powermate using the Starizona Filter System so that I could image the Eskimo Nebula using the Optolong HA, OIII, and SII filters. Focused on the star Pollux with the HA filter using the Meade Bahtinov Mask.

2008 MST: High Precision ON. Slewed to NGC2392.

2011 MST: StarLock ON.

It was a challenge getting the Eskimo Nebula centered in the camera field-of-view due to the high magnification I was using and the faintness of the Eskimo Nebula. I finally managed to get it pretty well centered as seen in this photo (StarLock autoguided, 1 minute, ISO 6400, WB 5560K, no filter).


I then began doing StarLock autoguided ISO 6400 WB 5560K exposures. Exposure times were HA: 2 minutes, OIII: 2 minutes, and SII: 8 minutes. This is the resulting image after merging (and cropping) the three exposures in Photoshop.


I am still learning to use the SHO filters and post-processing the different narrowband images.

2050 MST: StarLock OFF, High Precision OFF.

Viewed NGC2392 (Eskimo Nebula), 163X.

Viewed NGC2261 (Hubble's Variable Nebula), 163X.

2109 MST: clouds were appearing in the southern and western sky.

2114 MST: LX600 OFF.

2118 MST: took a SQM reading through thin clouds.

Just as I was preparing to leave the observatory there was an electrical brownout. The Tesla Powerwall we installed last summer picked up the load in the house and observatory. There have been a lot of brownouts and long duration power outages here recently. Our electrical utility company is run by the Federal Government (US Department of the Interior, Bureau of Indian Affairs). When we first moved to Oracle the power was pretty unstable, but then improved over the years. However, it seems to be deteriorating again.

Close: Thursday, 13 February 2020, 2130 MST
Temperature: 47°F
Session Length: 3h 24m
Conditions: Thin clouds, SQM 21.04

The International Astronomical Union (IAU) has released a statement on the satellite mega-constellations by SpaceX, Amazon, and others: Understanding the Impact of Satellite Constellations on Astronomy.

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