W. Watson wrote:
My understanding of the focus knob found on SCTs (all?) is that it is
attached to a long screw thet is on the back of the mirror. It would seem to
me that if one turns the screw CC that it would pull the mirror toward the
observer; thereby moving the focal point of the mirror inward. I tried this
with a 4" Meade SCT, and the focal point moves outward? Perhaps this depends
on where one things the head of a typical screw is in the device. I would
guess it essentially be where the focus knob is located. Can anyone clear
this up?

Don't know about the mechanics of the situation, but for the purposes
of star-testing, toward infinity is inside focus. This direction is
indicated on many SCT knobs.

--
Brian Tung
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