Why is my NexStar SLT optical tube slipping in altitude?

Your altitude clutch is slipping, causing the scope to droop in altitude. Remove the optical tube, unscrew the tube clamp tightening knob as much as needed, and slightly tighten the nut that is attached to the mounting bar (under the tube clamp tightening knob). This will create more friction for holding the tube to the mount.

Updated 12/27/13