visual vs AP filters?
Posted 29 November 2012 - 03:09 PM
Thanks as always everyone
Posted 29 November 2012 - 04:38 PM
FWIW, I recently swapped out a LPR filter that was for visual use for an AP optimized one for my DSLR. I can immediately tell the difference in better contrast.
Posted 29 November 2012 - 07:06 PM
As far as the refocusing though I'm uncertain what you mean by the question. Refocusing for filters is more something you find in the monochrome CCD and LRGB filters or narrowband Ha, SII, OIII - and even then there are filters that are par focal meaning you don't need to refocus.
One shot color imaging you only need a good LP filter depending on what you are imaging with and how bad the light pollution might be... If you are in true dark skies - great! you don't even need that.
What type of CCD or camera are you thinking of using?
Posted 29 November 2012 - 09:06 PM
Posted 30 November 2012 - 01:24 AM
Posted 30 November 2012 - 01:50 AM
If you're currently using a D90 you don't need the UV-IR filter since that's already built in in the camera. The use of OIII and H-alpha filters primarily meant for visual use would still be a compromise. Because these filters aren't designed for imaging. The main reason the use imaging filters is that they are designed for this purpose. One important thing is their behaviour regarding reflections and halos. Something that would hardly ever be an issue with visual filters.
Posted 03 December 2012 - 07:15 PM