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D850 DSLR imaging: ISS; Ring, Dumbbell, Veil Nebulae; Mars

Posted: 10 October 2020

Open: Friday, 9 October 2020, 1802 MST
Temperature: 78°F
Session: 1534
Conditions: Clear

12" f/8 LX600 w/StarLock
2" 24mm UWA eyepiece
2" 5.5mm 100° eyepiece
2" 2X Powermate
2" 4X Powermate
2" UHC, HA, OIII filters


1807 MST: LX600 ON, StarLock OFF, High Precision OFF.

Mounted the D850 DSLR at prime focus, focused on Saturn, locked 12" mirror, tweaked finderscope alignment, and updated the AutoStar with the latest TLE for the International Space Station (ISS).

1820 MST: all was now in readiness for the upcoming ISS pass which would start in 3 minutes. (That was it cutting closer than I normally prefer.)

1823 MST: the ISS pass started. Tracking was pretty good this pass. I did a video recording (1080p, 60fps) at 1/1600sec, ISO 1600. As the pass was essentially from horizon to horizon and passed through the zenith, it was a long bright pass. I had to frequently rotate the observatory dome to keep the ISS in sight, but I briefly lost it when it was near the zenith (and at its closest line-of-sight). These are some frames from the video showing the perspective change over time as the ISS passed from the northwest to the southeast.


1838 MST: viewed Jupiter and the four Galilean Moons nicely lined up on one side of the planet's disk, 102X. Then viewed Saturn, 102X. Seeing was better this night than on the previous session.

Mounted the D850 DSLR at prime focus of the 12" telescope using the Starizona Filter Slider System.

1847 MST: dome OFF (onto the PZT).

Relaxed on the observatory patio bench for a few minutes while waiting for Astronomical Twilight to end (1919 MST).

1911 MST: focused on the star Altair using the Meade Bahtinov Mask, locked the mirror, and turned High Precision ON. I did some focus tests using the Explore Scientific 2" UHC, and Optolong 2" HA and OIII filters. The UHC and OIII filters had essentially the same focus position, while the HA was only slightly different. I used the UHC focus position.

1923 MST: StarLock ON.

I then did StarLock autoguided imaging (ISO 6400, White Balance 5560K) of several nebulae. First I imaged M57 (Ring Nebula). During post-processing I merged the UHC image (1 minute, left) and HA image (2 minutes, right). The merged image (cropped) shows some slight trailing.

photo photo

Next was M27 (Dumbbell Nebula). I used the UHC filter (3 minutes, left), HA filter (4 minutes, middle), and the OIII filter (3 minutes, right) with the resulting merged image (cropped).

photo photo photo

I then imaged NGC6960 (Western Veil Nebula) using all three filters (5 minutes each): UHC filter (left), HA filter (middle), and the OIII filter (right) with the resulting (not cropped) image.

photo photo photo

Finally I imaged NGC6992 (Eastern Veil Nebula) using all three filters (5 minutes each): UHC filter (left), HA filter (middle), and the OIII filter (right) with the resulting (not cropped) image.

photo photo photo

2058 MST: StarLock OFF, High Precision OFF.

2105 MST: viewed Mars, 102X and 443X. The South Polar Ice Cap has decreased in size a lot over the past week (it is Summer in the Martian southern hemisphere).

2110-2137 MST: relaxed on the bench to enjoy the night sky while waiting for Mars to rise higher. Using the Vortex 12x50 binoculars I viewed M31 (Andromeda Galaxy) and its satellite galaxies M32 and M110, M33 (Triangulum Galaxy), M45 (the Pleiades), and the Double Cluster).

Mounted the D850 DSLR at prime focus + 4X Powermate + 2X Powermate.

2145 MST: took this single image of Mars (1/250sec, ISO 3200, WB 5560K, cropped). The South Polar Cap is barely visible at the bottom with Syrtis Major the prominent dark feature.


This is a stack of 3633 video frames (1080p, 60fps, 1/250sec, ISO 3200, WB Auto).


2156 MST: ended imaging.

Viewed Mars, 102X, 203X, 406X, and 813X. The best view was at 203X although 406X was still pretty good. I added one of the Variable Polarizing filters for the views at 203X, 406X. and 813X. This improved the view, especially at 406X, by reducing the brightness of the planet as it approaches opposition next week. Laurraine came out to the observatory to observe Mars, 203X + filter.

2220 MST: LX600 OFF.

2223 MST: dome ON.

2230 MST: took a Sky Quality reading and reported the result to Globe at Night.

Close: Friday, 9 October 2020, 2238 MST
Temperature: 68°F
Session Length: 4h 36m
Conditions: Clear, SQM 21.14

If you are concerned about the impact on astronomy from megaconstellations of satellites like Starlink, check out this article on what is being done by the professional astronomy community: Astronomers hope UN can help protect dark skies against megaconstellation threat.

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