25.09.2021 Base ring arcs + imaging:

 *

Saturday 25th 60F, overcast clearing to rather cloudy later. 

First I laid out the bottom layer of the base ring on the ground. A tarpaulin kept the plywood dry. I have marked off the overlaps at an angle to ensure there are no weak joints. Need to cut them next. Then a second layer, with staggered joints, will have to be marked out.

11.50: Imaging. Two ARs with groups of spots. AR2871 in the south. AR2872 in the northern hemisphere. Seeing, between clouds, is fairly steady and modestly transparent. Say 3/5 for both. If only I could maximize these conditions.

Yet again I am struggling with the PST etalon,  sweet spot ring. I am getting very strange results despite not changing anything between captures. Nor during processing. The images look superficially sharp but don't bare close examination. 

13.05 [CET] Improved the tuning by clocking the blocking filter against the etalon. Better spread, but still a darker stripe across the image.

13.13 AR2872 Horribly off-band in the south east corner.

 

 

 

 

 

14.18 A mixture of dark and light.

Thin, high cloud has taken over from the bigger and denser clouds. It has spoiled the transparency.

 

 14.27 Still uneven lighting and off-Ha band areas.

Changed to 1.6x GPC for a wider view. Probably not helpful when it comes to etalon sweet spots.

It doesn't look like it but the 5kg weight really is in the middle of the circle. A radius bar pivots on a 10mm bolt. I used a weight to avoid making further holes in the lightweight tarpaulin.

All the skewed joints of the 8.5 arcs of the first layer have been cut on the miter saw.

 

 

16.20  Returned from cutting the joints for the first layer of the base ring. Where there is no obvious cloud the sky is white. 

 

 

 

 

 

*