[ATM] How would you mount a secondary in a LHN?

["Christopher Dalla Piazza" <dalchri@hotmail.com>]

I am getting ready to design the secondary holder for my Lurie-Houghton 
Newtonian so that I can figure the corrector to primary spacing and finalize 
the radii for my corrector lenses.

Other designs I have seen make a trepaning core of the same diameter through 
both lenses.  Then a sleve is inserted through both positive and negative 
lenses and a spacer is inserted in between.

Given that the Lurie-Houghton has a two lense corrector, I am a little 
apprehensive about pinching the two lenses together because of the air space 
at their center.  What I am considering is trepaning the negative lense with 
a larger diameter core than the positive lense because the positive lense is 
thicker at its center.  This way, the secondary is only supported by the 
positive lense.  I don't have to worry about creating a spacer that has the 
exact thickness necessary.

What would you do?


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