Fixed % density filter?
Posted 27 July 2019 - 12:57 PM
I'm looking at buying a fixed neutral density filter like 25%, 50%, or 75%. Which one do you use the most?
Posted 27 July 2019 - 01:01 PM
Depends on the size of the OTA being used (14" requires more the 8" to equal brightness).
The 25% should do well for the 8" SCT
For multiple OTA's I found a variable Polarizer best as It can be set from 0% - full and anywhere in between.
I used it on the Diagonal nose-piece which requires trial/error to get right.
Posted 27 July 2019 - 01:56 PM
For a 10 inch dob, I use a 25% filter. The 13% is too dark. I only have to use the filter if panning around at medium power.
High power is comfortable enough when I get to 1mm exit pupil or below. I bought a variable polarizer thinking maybe polarized light would allow me to see more detail over a simple ND. It doesn't