The Lower Cover
This is a cloth cover that can be easily attached when warm air currents from your head creep over the backplate and into the light path. The cover slips over the end of the telescope and is pulled around the back end and the upper and lower draw strings tightened and adjusted.
Telescope is seen here with and without the cover on its temporary test mount. The actual base plate can be seen at the bottom of this page with a Losmandy dovetail plate.
Back end and underside. Note drawstring for easy tightening and adjustment.
The cloth is a cotton weave that allows warm air to slowly escape and prevent tube currents but also prevents rapid infusion of body heat.
Actual base plate and Losmandy dovetail plate.