Hi,
Have for [strike]sale[/strike]... trade an adapter for double stacking Coronado SM90 filters. This was made for me to use with two, not factory matched etalons to find the best position of one to other etalon with no fear that front etalon will fall off. I have two adapters so one I can give to someone who needs something like this
I'd like to trade it for some Explore Scientific 82 deg. eyepiece. Let me know what you have