Long focus mirrors?Posted By dan hilts |
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The difference between the best fit parabola and a spherical surface on an 8" F20 mirror is only 0.011 waves error. You could never reliably measure this, let alone work to it.
A good sphere should do.
clear skies,
dan
The difference between the best fit parabola and a spherical surface on an 8" F20 mirror is only 0.011 waves error. You could never reliably measure this, let alone work to it.
A good sphere should do.
clear skies,
dan