Hi all. I've just picked up a second hand 8"dob and having a bit of trouble with crisp focus. Noticed that the mirror is fairly dirty, but don't want to fudge everything up by pulling the base off without asking for advise. The base has three Philips head screws and three hex key grub screws. Advise would be greatly appreciated. Thanks heaps.
Hi Mate there has been a few threads on this topic. Here is a Youtube video its method I also use.
When you reinsert the mirror back in the cell don't tighten the three clips. There should be a void to put a piece of paper between clip and the mirror surface.