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Working out effective Dia. for given exit pupil?
Hi all,
I am aware of the idea of looking to maintain an exit pupil to a maximum of 6 to 7mm. Anything larger & we reduce the amount of light entering through the pupil and this in turn will act to effectively reduce the objective's/mirror's diameter.
But how can this be worked out mathematically?
I'll give one of my scope's & EP's as an example to work on:
Scope: 17.5", f/4.5, fl 2000mm
EP: 65mm
Mag: 31X
Exit pupil: 14.4mm
Alex.
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