ATM Re-assembling a Mak

[Anthony Stillman <atmer@flash.net>]

The recent Questar thread got me wondering about Maksutov tolerances.  To
investigate, I plugged Rutten and van Venrooij's f/15 Rumak into OLSO LT.
Then, looking at the MTF, spot diagram, and wavefront, I twiddled tilt,
decenter, and piston.  Each twiddle was done independently. The values
listed below produced tolerable degradation.  I refocused when pistoning.

Some of the tolerances are quite touchy.  Assuming optical threading on the
positioning screw, the adjustments would be in the tenth of a turn regime.
Quite do-able, with the proper collimating technique and a quality jig.

Anthony



Corrector
  Tilt         0.01 degrees
  Decenter     0.02 mm
  Piston       > 50 mm

Primary
  Tilt         0.05 degrees
  Decenter     1 mm
  Piston       > 50 mm

Secondary
  Tilt         0.05 degrees
  Decenter     1 mm
  Piston       ~ 10 mm