View Single Post
  #3  
Old 07-05-2021, 06:12 PM
kosborn (Kevin)
Registered User

kosborn is offline
 
Join Date: Mar 2018
Location: Canberra
Posts: 348
HI Alex,


I started with 31mm ZWO narrowband filters with an ASI1600mm and found there were horrible internal reflections as the filters are anti-reflective on one side only. I ended up replacing them with Astronomik filters which work really well. From the reading I've done, 31mm filters are the smallest possible for the ASI2600mm, depending on your focal length. Probably 2" is the best way to go. This web page: https://astronomy.tools/calculators/ccd_filter_size has a good calculator to work out minimum filter size for your set up.


Kevin
Reply With Quote