7.11.2020

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7th November 10.45am[CET] 52/50F. Southerly breeze with northerly direction of cloud movement. Overcast start, slowly clearing to blue patches. Still waiting to centre, tune  and focus. 

11.00 Have captured some very unevenly illuminated videos with the 2x GPC. Now changed to 1.6x to bring in the entire spot group + large AR region to SE. Trying to tune out the offset dark and light by manual tilting and rotation of the etalon cell. Needs patience because the sky is not remotely clear! Less than one second to adjust each time between clouds. Minutes between clearances.

I saw a single dark spot in the north east quadrant while trying to centre the large AR group in the southern hemisphere.

The seeing is weird. Thermally mobile and soft again. It doesn't look transparent but I'm getting detail.

I am getting rather strange [flat] images compared with before wrapping the etalon. I also reversed the etalon and had sharper images.

The wind has picked up so I have netting stretched across the slit just below the light path.

12.04 Still struggling with off-axis lighting but getting improved sharpness near the centre.

If you could see the cold, grey, solid overcast and windy day here you wouldn't think it possible! The image on the monitor is soft and wobbling in the wind and atmospheric convection currents.

A three second hole in the clouds is all it needs to capture 500 frames. I'm using my iStar 150mm aperture achromat with H-a correction. F/10, 1500mm f/l, PST etalon, SharpCap, 800x600, 151fps, 6.6ms exposure, Gain 54. ZWO ASI174MM mono camera with a cheap 1.6x GPC/Barlow on the camera nose. 

Stacked in Autostakkert using 75 frames of 500 and then sharpened in ImPPG. I finally process the image in PhotoFiltre. Which is a simple, image handling software. Mostly balancing Gamma with Histogram to bring out the most detail and adjust overall brightness. 

Further sharpening is not usually possible because it just makes the image spotty. I often Crop the image for the best composition and resize to 600 pixels max dimension, if it falls short of that figure. The second image of these two has been sharpened and brightened with Gamma.

12.30 52/49F, cold and breezy in the dome. No sun for over 1/4 of an hour! Time to check if lunch is ready. 

14.30. 51/49F Sun is back out again. Cold in the dome. Cloud bank crossing the sun. The seeing is now unbelievably bad! Altitude only 11° and above the house roof. Complete waste of time. The sun hasn't reappeared. The video and processed image were surreal!
 

15.10 The sun came out and looked like it was under a fast moving stream on the monitor. Eek!

 

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