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More Comet C/2022 E3 (ZTF) imaging

Posted: 2 February 2023

Tuesday night, 31 January 2023, was partly cloudy. The sky cleared about sunset on Wednesday, 1 February.

Open: Wednesday, 1 February 2023, 1814 MST
Temperature: 45°F
Session: 1828
Conditions: Mostly clear, breezy

12" f/8 LX600 w/StarLock
2" 24mm UWA eyepiece
2" 30mm eyepiece
2" 9mm 100° eyepiece
Focal Reducer

iPhone 13 Pro Max

1818 MST: LX600 ON, StarLock OFF, High Precision OFF.

Viewed the planets Venus, Jupiter, and Mars, 102X.

Viewed the waxing gibbous Moon, 102X and 81X.

1839 MST: Took this handheld iPhone 13 Pro Max photo of the Moon projected on the observatory dome from the 12" telescope at a magnification of 81X. Used the iOS Camera app (Night Mode, 3 seconds, 1X lens).


1842 MST: Local Oracle amateur astronomer David C. arrived. He wanted to see how I did astrophotography.

Attached the LiDAR cover on the iPhone and mounted the iPhone on the 30mm eyepiece using the Levenhuk adapter.

1908 MST: iPhone photo of the Moon, afocal 81X, taken with the iOS app NightCap Camera (ISO 34, 1/4400sec, 1X lens).


1917 MST: Observatory Wi-Fi ON.

Used SkySafari 7 Pro on the iPhone to GOTO Comet C/2022 E3 (ZTF).

1920 MST: StarLock ON.

1922 MST: StarLock autoguided iPhone afocal 81X image of Comet C/2022 E3 (ZTF) using NightCap Camera (Long Exposure, Light Boost, ISO 12500, 15 seconds, 1X lens).


Removed the iPhone and eyepiece from the 12" telescope. Mounted the D850 DSLR at prime focus + focal reducer, focused on the star Capella using a Bahtinov Mask, and locked the 12" primary mirror.

I then began imaging Comet C/2022 E3 (ZTF). At the end of my imaging run I discovered that I had (once again) forgotten to remove the Bahtinov Mask from the telescope! Phooey! Here's an image with the mask.


1955 MST: Wi-Fi OFF.

1958 MST: I removed the mask and began imaging the comet again, StarLock autoguided, 15 seconds exposure, ISO 12800, at one minute intervals. Here is the first image and an animation sequence showing the comet's rapid motion. The bright moonlit sky interferred with imaging the comet, which is still faint.


2004 MST: StarLock OFF.

Viewed the comet, 102X and 271X.

2015 MST: Viewed the comet, 12x50 binoculars. Dust tail was obvious.

2029 MST: LX600 OFF.

David left.

Close: Wednesday, 1 February 2023, 2036 MST
Temperature: 41°F
Session Length: 2h 22m
Conditions: Clear

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