2018 February 12 Sun - AR12699 & prominence

[PTS]

2018 February 12 Sun - AR12699 & prominence

Since the tilt by using a single washer does not produce enough tilt angle, I am using the same tilted setup as yesterday, thus all the fringes remain the same. I cannot just add more washers as the locking screw is not long enough, and I don't have 1/8-inch bolts on hand (we only have stock of mm bolts & nuts). A new tilt mechanism is being made but it takes time. Hopefully this jig can be made tomorrow.

AR12699 remains very active, with a strong flare at around 03:00 - 03:10 UTC.
On the solar limb, 2 faint prominences show up on the SWW limb, with another on the NNE limb.

Telescope: AP Starfire EDT 155 mm f/9.
stopped to 50 mm (f/28) for disc images, with 4X telecentric lens (f/36) for closeups
filter: Solar Spectrum SO1.5/0.3A with CERF prefilter
Camera: ASI1600MM, 4656X3520 pixels (3.8 micron)
North is up, east is to the left.

[PTS]

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[Eddy So]