Thursday, 29 December 2016
When Less Is More in Solar Imaging - Ha Full Disk 29th December
I've been messing around with a PST for some time now since the summer, first double stacking it with a Lunt 50 etalon, the BF5 has been replaced with my BF10, as IMHO, this particular filter offers better contrast. I've also shortened the eyepiece holder on the PST, so that all the usual issues of cameras not coming to focus without a barlow etc are a thing of the past. Today, in my new found hour long winter season viewing window I tried a different experiment, which barlow offered the best view. I had 2 to choose from, my astro engineering magnimate and a bog standard Skywatcher 2x barlow. The PGR Chameleon 3 with its 2048x1536 pixel sensor offers plenty of real estate for such an exercise. After taking numerous images the results kinda didn't surprise me, the best image was the one without a barlow at prime focus, it was noticeably sharper, with more contrast and more fine detail. It gives a 1200 pixel wide disk, which, for displaying via the web is ample. I still need to get the perfect tilt with the Daystar Interference Eliminator, I feel some index marks coming on. Next steps may have to be to lose the PST Black Box (and it's potentially astigmatic) penta prism assembly and have a focuser directly on the back of the etalon. With the correct spacings it should work well!
Posted by Mark Townley at Thursday, December 29, 2016