Adjusting screws for the viewfinder of an 11 inch SCT f/10, standard thread | Bob’s Knobs

An 11-inch Schmidt-Cassegrain telescope allows you to easily check the collimation when zooming in. Adjusting it with a screwdriver just before the large corrector plate feels uncomfortable. With these adjustment screws for an 11-inch SCT f/10 telescope from Bob’s Knobs, you replace the collimation screws with screws with a large knob, so you can adjust with your fingers.

This set has standard thread. If you use a Celestron C11 on AVX mounting or another 11 inch SCT, then check beforehand which thread your telescope has.

Replace the screws one by one so that the mirror stays in place, and then collimate on a defocused star at high magnification. How to do that, you can read in our explanation on adjusting the telescope.

With metric wire there is a 11 inch set with metric thread, and for a 11 inch with Fastar one Separate Fastar version.