Hi Matt
Here is the FOV for the C9.25 at F10 (Prime Focus) with my Pentax *ist DS DSLR.
I have also been trying to compare the imaging performance of the C9.25 with a full aperture solar filter and my Vixen ED102S 4” F9 refractor with a full aperture solar filter. Due to clouds and time constraints, I haven’t been able to image through both systems on the same day, at the same time.
However, here is a C9.25 F10 Prime Focus image from 24 Oct (2350mm fl) compared to a Vixen 102mm f9 with x2 Barlow image from 25 Oct (1840mm fl). Both were taken with the Baader Astrophotography Solar Film (3.8) and the Philips ToUcam. I estimate that the seeing was around 4 to 5 out of 10 for both images.
- The C9.25 was difficult to focus and the image on the screen never really looked sharp during the avi capture.
- Finding focus with the Vixen refractor with x2 Barlow was markedly easier and there were several fleeting moments of reasonable clarity during the avi capture.
I would like to take side-by-side images with the C9.25 at F10 (2350mm) and the Vixen 102mm with my x2.5 Powermate (2295mm) and compare the results. But – there are no sunspots on the Sun right now…..
So, based on this single sample, it does appear that the 102mm refractor out performs the C9.25 during mediocre seeing in the day time. I know there are other factors to consider, such as “was the C9.25 perfectly collimated", "was the seeing the same", etc, but interesting early results I would say.
Cheers
Dennis