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Re: ATM Analysis of Nasmyth/Cass in OSLO Lt




Pat Ferrick wrote :

> I finally managed to get a design for a Nasmyth-Cassegrain telescope
...
> Spot size:         0.012 mm (8% larger than the diffraction limit)
> Wavefront error:   0.05 waves RMS, 0.16 waves peak-to-valley

Why residual wavefront errors ? With perfect paraboloid/hyperboloid
you should be way into 1/1000th of a wave of residual error...?

> Astigmatism:       0.6 waves (S and T)

How did you manage to get astigmatism on axis ?

Something's wrong here ...?

Bratislav