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Re: [ATM] Crayford focuser protrusion problem
John,
Not at the low power these eyepieces give you. Don't worry about it.
Scott Ewart
To the ATM listserv:
I plan to use a JMI DX2 2" Crayford focuser with my
future 8" f/6.25 reflector telescope, and a telescope
tube with an inside diameter of 9.375". Based on the
focusers' low profile and 1.25" travel range, and
eyepieces that I plan to use with this telescope, I've
determined that some (longer focal length eyepieces)
will cause the drawtube to protrude into the telescope
tube by approximately 0.4".
This is with a focal plane at 0.8" above the fully
racked in position (1.6" height off of the telescope
tube). Shorter focal length eyepieces require the
margin I have left beyond this point. My question
is: Will the 0.4" protrusion of the drawtube cause
undesireable effects that I should try to correct?
Thanks for any advice.
John Lynch
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