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ETX-125AT Observing and iPhone Astrophotography

Posted: 17 December 2019

Wind continued on Sunday, 15 December 2019. Monday, 16 December, was mostly clear.

Open: Monday, 16 December 2019, 1759 MST
Temperature: 46°F
Session: 1415
Conditions: Mostly clear

1.25" 26mm eyepiece
1.25" 40mm eyepiece

iPhone 11 Pro Max

While waiting for the observatory electrical outlets to be replaced by my electrician, I continued to use my older telescopes. This session I used my Meade ETX-125AT (from 1999). I set it up on the observatory patio.

A Celestron Power Tank was used to provide power to the ETX-125.


1809 MST: ETX-125AT ON.

Viewed Saturn, 73X, low and behind a tree. Not a great view but the Ring was visible. Then viewed Venus, 73X. The gibbous phase was visible.

Since I had a swapped the AutoStar #497 from my ETX-90AT to the ETX-125AT I was getting "rubberbanding" when doing GOTOs with the ETX-125. I did a CALIBRATE MOTOR and TRAIN DRIVES which cleared the rubberbanding.

Viewed M57 (Ring Nebula), 73X. Nice view.

I then began preparing to do some iPhone afocal astrophotography. I mounted the iPhone 11 Pro Max on the 26mm eyepiece using the Meade Smartphone Adapter. Unfortunately, Alt/Az tracking was not good enough this night to allow long exposures using the iOS app NightCap Camera.

I switched to the 40mm eyepiece (48X) and viewed the pretty double star Albireo. Then viewed M27 (Dumbbell Nebula), 48X. Nice.

Viewed the Double Cluster (open star clusters), 48X. Pretty view.

Mounted the iPhone 11 Pro Max on the 40mm eyepiece using the Levenhuk Smartphone Adapter. Took this afocal 48X image of the Double Cluster using NightCap Camera (Light Boost, ISO 12500, 1sec, 1X lens).


Slewed to M45 (Pleiades) and took this afocal 48X image with the iPhone and NightCap Camera (Light Boost, ISO 12500, 1sec, 1X lens).


Only part of the Pleiades is visible in the image.

By this time I was getting cold. (A freeze warning was in effect for the overnight hours.)

I took a quick look at the Pleiades and then M31 (Andromeda Galaxy), 48X. The view of M31 was very nice. Its satellite galaxies M32 and M110 were easily seen.

1908 MST: ETX-125AT OFF.

Close: Monday, 16 December 2019, 1915 MST
Temperature: 40°F
Session Length: 1h 16m
Conditions: Clear

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