I LOVE finding out about different ways to appreciate the Sun and light in general. Use this forum to post your info or questions about various outside the mainstream ways to appreciate our life giving star!
http://brierleyhillsolar.blogspot.co.uk/ Solar images, a collection of all the most up to date live solar data on the web, imaging & processing tutorials - please take a look!
These are very detailed. What effect does the 3600l/mm grating have on light throughput? I would imagine you need to use higher gain or exposure settings?
If you are using our SHG v4.3 software and a 3600 l/mm grating, you should take note of the new feature called "Ellipse fit shift". The default for this is 10 pixels, but that was chosen based on the assumption of using a 2400 l/mm grating. With the higher dispersion of a 3600 l/mm grating, you need to double this to 20 pixels or the ellipse fit routine may have a problem, particularly with Ca-K/H. I assume if you use a 1200 l/mm grating, you might want to reduce this to maybe 5 pixels.
I had thought maybe the slightly non-circular shape of the H-beta might have been due to an ellipse fit issue as a result of the high dispersion grating. But I suspect it is actually that your mount scan was slightly irregular.
"Stubborn transversalium" is something to use if the problem is obviously transversalium (due to a stubborn bit of dust on the slit). Your slit looks quite clean. There is noise in the Ca-H image, but this is likely because you needed to use a longer exposure and slower scan (I assume).
Between v3.7 and v4.3 there were a lot of little improvements. I don't expect there will be any further updates until the spring due to work and university commitments. I would strongly recommend using the most recent version (v4.3). The file handling is much improved and it also now runs multithreaded so it is quite a bit faster if processing multiple files.
Would be interesting to see the results you get in CaK stopping the 66 down to 40mm John, I suspect it will be quite an improvement.
http://brierleyhillsolar.blogspot.co.uk/ Solar images, a collection of all the most up to date live solar data on the web, imaging & processing tutorials - please take a look!
