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Re: [ATM] back to longer FL
>The FL of the second 12 inch f/5 mirror for the binoscope I want to build is
>1.2% shorter at the moment >
Aloha Jan,
Perfect matching of the focal lengths, while ideal, may not be
necessary or even warranted. Having measured the EFLs of many groups
of commercial eyepieces in contemplation of purchasing on contract,
well over one percent variation in EFL is normal and is to be
expected. Bino considerations in not using up processor (brain)
accommodation require that the magnifications be equal, and matching
eyepiece EFL to primary focal length can yield practically perfect
magnification match.
Measure your eyepieces and position them accordingly, or select them
from your suppliers' stocks.
Your home page is splendid!
Doei,
Stan
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