20021003

Camera block, after holes bored, top peaked, and bottom F/17 bay opened up. the bore holes, are, from bottom to top, the F/5 camera path, the F/17 camera path, and the pupil viewer camera path.
Underside view of camera block. The F/17 dogleg bore holes are just visible. They allow the much longer F/17 camera path to be folded using four mirrors into the camera block space.
View from bottom of Camera block to show bore holes for F/17 folded beam path. Inside the bore holes are flat reference surfaces against which lens cells are mounted. Inside all the bore holes, anti-reflection "rifled" baffle tubes are snugly fit. These control stray light in this confined beam path.
THK lead screw drive system (aka "rail") mounted to the bottom of the camera bay in the filter box. The two rectangular aluminum bars under the THK rail hold the ball bearings and sockets comprising a 3-point kinematic mount. The square aluminum plate on top of the rail is bolted to the two "cars" that ride the rail (one car captures the screw, one car is free of the screw). This plate also has sockets for a 3-point kinematic mount