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Focus


Table 3.13: Focus Specifications
Drawing: RCT001/3
EOS Drawing: SCH-4026-1
Motor:  
Motor Encoder:  
Overall Encoder: Heidenhain M12 or MT2571 linear encoder which is ENC#5
Limits: two-level in and out limits
Controller: PMAC#5
Drive Amplifier: Amp 5
Homing: positive motion away from primary.
  home is almost to the far limit
Scale: 20,000 counts per millimeter
Video camera: -120700 counts
Range: -435000 $ -> +$ 3500 full range 21.925
  -425000 $ -> +$ 1000 useful 21.3 mm

Note: It takes about 7 minutes to home. It seems that the camera focus is around -5.8mm.

(02Apr2003 statement focus=-99300 -0.21mm is a good focus).

Figure 3.20: Photo of the Focus
Image Secondary


next up previous contents
Next: The Great White Spot Up: Telescope and other Devices Previous: The Finder   Contents
Louis-Gregory Strolger 2012-01-09