The Parfocal Ring
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It is extremely useful to have the LPI camera and a telescope eyepiece be parfocal—it will save you time when
you need to refocus.
Parfocal means setting two or more eyepieces to the same focus. (In this case, one eyepiece is a camera.) In
other words, if you focus one eyepiece in your telescope, then you remove it and replace it with a parfocal
eyepiece, the parfocal eyepiece will require little, if any, refocusing.
The following procedure will show you how to make your LPI camera parfocal with a low-power wide-field 25mm
or 26mm eyepiece (do not perform this procedure with a high-power eyepiece). Use the supplied parfocal ring
and perform the procedure during the daytime.
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