Before moving to 2 inch filters this was my favourite. The tech stuff below
Astronomik H-Alpha CCD Filter is a photographic filter mounted in a 1.25" threaded cell
Designed with the finest technical standards in mind to permit the desired optical performance for deep sky CCD imaging
Allows H-Alpha light emissions to pass while blocking almost the entire remainder of the visual spectrum plus IR
The Astronomik H-alpha CCD Filter features a 12 nm FWHM
Blocks all undesirable light pollution and is ideal for imaging planetary nebulae and supernova vestiges and German-made.
Price $100 posted Australian Buyers only.
regards
Dennis
Last edited by dennisjames1; 03-05-2024 at 03:52 PM.