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Sun imaging, Sunspot AR2786

Posted: 28 November 2020

Open: Saturday, 28 November 2020, 1058 MST
Temperature: 62°F
Session: 1561
Conditions: Clear, windy

12" f/8 LX600 w/StarLock
2" 24mm UWA eyepiece
2" 50mm eyepiece
2" 9mm 100° eyepiece
2" 5.5mm 100° eyepiece

iPhone 11 Pro Max

Although the wind was blowing strong at times I wanted to do some imaging of the Sun through the 12" telescope. I attached the Thousand Oaks Optical solar filter on the 12" telescope before opening the observatory dome.

I then used solar eclipse glasses to view the Sun. Sunspot AR2786 was barely visible as a very small dot with the unaided eyes.

Next, I then set up the iPhone 11 Pro Max for imaging of the Sun using the Spectrum Telescope 8X Telephoto Lens with Solar Filter.


This iPhone image was taken with the 1X lens and 8X telephoto using the iOS app NightCap Camera (ISO 32, 1/180sec). The image is very similar to what I saw with the solar eclipse glasses. Sunspot AR2786 is just below the center of the Sun's disk.


This iPhone image was taken with the iPhone 2X lens and 8X telephoto using NightCap Camera (ISO 200, 1/400sec).


1132 MST: LX600 ON, StarLock OFF, High Precision OFF.

Viewed the Sun, 102X, 271X, and 443X through the 12" telescope with the solar filter attached. The best view of sunspot AR2786 was at 271X.

I mounted the D850 DSLR at prime focus. Focusing the image was a challenge due to the wind and atmospheric turbulence. This uncropped image of the Sun (1/1000sec, ISO 400) shows the large sunspot AR2786, the smaller sunspot AR2785 to its right, and a very small sunspot AR2783 (at 3 o'clock on the Sun's disk).


I tried imaging at higher magnifications but seeing was not good enough. This is a cropped image of AR2786 from the full-size image above.


Took a final look at the Sun, 49X and 102X.

1234 MST: LX600 OFF.

Close: Saturday, 28 November 2020, 1243 MST
Temperature: 82°F
Session Length: 1h 45m
Conditions: Clear, breezy

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