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Galaxy Imaging:
NGC3344, NGC3351 (M95), NGC3371, NGC3373, & M105

Posted: 31 May 2019

Open: Thursday, 30 May 2019, 1856 MST
Temperature: 80°F
Session: 1357
Conditions: Clear

Equipment Used:
12" f/8 LX600 w/StarLock
2" 24mm UWA eyepiece


During the day it occurred to me that maybe the StarLock autoguiding issues I have been experiencing were due to a scope balance issue and not poor seeing. I had suspected poor seeing was the culprit as the astronomical seeing forecasts always showed poor seeing for the times I was imaging. A few weeks ago I had reconfigured the LX600 counterweights. To eliminate that as a factor I repositioned one of the counterweights before this night's imaging attempts, with poor seeing still in the forecast.

1908 MST: relaxed on the observatory patio bench.

1927 MST: sunset.

2000 MST: back in the observatory. Prepared D850 DSLR for prime focus imaging.

2006 MST: LX600 ON, StarLock OFF, High Precision OFF.

Slewed to the star Regulus and SYNCed the AutoStar.

2030 MST: mounted the D850 DSLR at prime focus, focused on Regulus, and locked the 12" primary mirror.

2042 MST: High Precision ON.

2044 MST: StarLock ON.

Began imaging galaxies. Still had poor StarLock autoguiding even with rebalancing the telescope. I also SYNCed the AutoStar on an object, something I had not done since first receiving the LX600 in 2016, but that didn't help. So apparently poor seeing was still the culprit as I could not get exposures longer than 1 minute. I managed to get these StarLock autoguided, 1 minute, ISO 6400, White Balance 5000K, exposures:


NGC3351 (M95)

NGC3371, NGC3373, and M105

2130 MST: StarLock OFF, High Precision OFF.

Gave up imaging. One other possibility remains for the poor StarLock autoguiding: a corrupted PEC (Periodic Error Correction) model. It has been a long time since I did a PEC modeling (using the StarLock). I hope to redo the PEC modeling in the coming nights.

Viewed NGC3371, NGC3373, and M105 galaxies, 102X.

Viewed Jupiter and its four Galilean Moons, low in the southeast (and through a tree), 102X.

2144 MST: LX600 OFF.

Close: Thursday, 30 May 2019, 2156 MST
Temperature: 67°F
Session Length: 3h 00m
Conditions: Clear

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