thats the main issue im having after using the coma corrector. Im not blaming the coma corrector. I think it helps me to determine to find the correct collimation point. I can get circle stars, but the diff spikes will be doubled meaning that im not focused.
Also seriously consider buying a copy of "New Perspectives in Collimating a Newtonian" by Vic Menard and Tippy D'Auria. It's about $15 U.S. and is widely considered to be "the" reference.
