During my last several Barnard Objects Project (dark nebulae) imaging sessions I had noticed that slew accuracy had been decreasing. This resulted in these faints objects being near or beyond the edge of the camera field-of-view. I had been trying to compensate for the pointing errors by adjusting the camera FOV westward (decreasing Right Ascension, RA), but I had been just guessing on the amount of adjustment needed. After the pointing errors on my previous session I decided to further investigate the situation. The error had increased as I moved northward in Declination in the list of Barnard Objects. The reason for the error is the different Epochs used by the AutoStar and the object coordinates in the list. Previously when GOTOing the northern Barnard Objects I had been slewing in RA about 35 arcmin westward than the listed coordinates. After comparing my recent images to the reference images on the Grasslands Observatory Barnard Objects website I determined I would need to slew further westward by subtracting an additional 15 arcmin from the object Right Ascension. I did that on this session, with the results discussed below.

Unfortunately, this next session was delayed due to do forecasted clouds arriving on Saturday, 23 November 2024, and continuing until Saturday, 30 November. I attended the "Star Party & Holiday Toy Drive at Oracle State Park" that evening.

As I approached Cassiopeia Observatory after sunset on Monday, 2 December, the thin crescent Moon was visible very low in the southwestern sky. I took this iPhone 15 Pro Max photo (25X digital zoom).

Open: Monday, 2 December 2024, 1809 MST Temperature: 72°F

Session: 2042 Conditions: Mostly clear

Equipment:
12" f/8 LX600 w/StarLock
2" 24mm UWA eyepiece
2" 50mm eyepiece
2" 5.5mm 100° eyepiece
2" 14mm 100° eyepiece
Focal reducer

Camera:
iPhone 15 Pro Max
D850 DSLR

1815 MST: LX600 ON, StarLock OFF, High Precision ON.

Viewed Venus, then Saturn, 102X.

Prepared the D850 DSLR camera for imaging. Mounted the camera at prime focus + focal reducer, focused on the star Deneb, locked the telescope mirror, and slewed to the first Barnard Object. From my earlier "guestimate", I subtracted 15' from the published Right Ascension of B192. I repeated the same RA adjustment for B194, B195, and B196. Unfortunately, my guestimate must have been incorrect as none of the stars matched the reference images for these Barnard Objects. Back to investigating a solution for the pointing error for these northern sky Barnard Objects.

I then viewed M45 (Pleiades), 102X and 49X.

Attached the LiDAR Cover on the iPhone and mounted the phone on the 2" 50mm eyepiece using the 3-axis adapter.

1925 MST: StarLock ON.

iPhone StarLock autoguided image of the Pleiades taken with the Camera app (Night Mode, 30 seconds, 1X lens). Some nebulosity is visible in the image.

1944 MST: StarLock OFF.

Viewed Jupiter, 102X, 443X, and 174X.

Took this iPhone afocal 174X handheld image of Jupiter and the four Galilean Moons using NightCap Camera (ISO 3200, 1/120sec, 1X lens). The Great Red Spot is visible just below center of the planet's disk.

This handheld iPhone photo (Night Mode, 10 seconds, 1X lens) shows Jupiter and the Pleiades in the eastern sky.

2020 MST: LX600 OFF.

2026 MST: Took a Sky Quality reading.

Close: Monday, 2 December 2024, 2030 MST Temperature: 61°F

Session Length: 2h 21m Conditions: Clear, SQM 20.86

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