I recently acquired a Canon 200mm f/2.8 L lens to use with my ASI1600MM. I actually used to own this lens about 6 years ago and I'm really thrilled to be using it again - so far it is working out well.
Date: 11/17/2018 Mount: Astro-Physics Mach1GTO Camera: ZWO ASI1600MM-Cool Exposure: Astrodon Ha 1.25" 5nm : 33x300" (gain: 200.00) -20C bin 1x1