Quote: Put differently, is there an advantage to having the cell oriented the way yours is, or could I rotate the mirror supports 90 degrees, as long as the edge supports stay on the bottom?
Quote:Come to think of it - one reason for a 4 pt support (over 3 pt) is that I can place the supports on a larger radius than strictly optimum. I have the idea (right or wrong) that this improves stability, and also decreases the distance between back and edge supports, giving a shorter lever arm in case of friction between support and edge (with ball bearings, friction is negligible anyway). No hard data behind this, it just felt better...Nils Olof
Quote: BTW, is there a rule of thumb for 4-point cells like those for 3 and 6 point? IIRC the 0.4 and 0.6 were rather insensitive to being a little off, across a wide range of mirror size and thickness.