Luminance filter vs Wratten #12

Don’t be misled by deceptive marketing that promotes a refractor as “APO-like.” I fell for it because I am always looking for a good deal. Well, this deal didn’t pay off. In essence, I purchased an Achromat with ED glass. Frankly, I don’t know how much of an improvement the glass makes, but I recommend paying the price for an actual APO.

I have known for quite some time that my refractor cannot focus blue. Red is excellent, green is OK, but blue is a mess. Over two consecutive nights, I imaged M34. The left-hand image uses my standard Optolong luminance filter. The right-hand image uses a Wratten #12 (minus blue.) The comparison is stunning. Now all I need to do is figure out how to capture color!