Reticle eyepieces

Has anyone used these for non-astrophotography. I thought about purchasing the Celestron 12.5 microguide for measuring angles, crater diameters, separation of double-stars, planetary angular sizes, etc. Are these accurate? I would think this depends on the power you are viewing. I also see Tak has a 5mm reticle eyepiece, but I can't find much information one this product. Any help or suggestions would be great.

Thanks,

Rob

Rob,
I have the Meade "Astrometric" reticle eyepiece. They're accurate, but you need to do some calibration, via timings, for every scope you use them with. Due to the differences in focal lengths of scopes, each will measure a different amount. So what happens is, after you've calibrated the eyepiece to your scope, the gradient's might not be a nice round number, but more likely a fraction, like 1.3 arc seconds per gradient, etc. The eyepieces come with instructions on how to calibrate them.
--
Scott Baker
Vice President, New Member Mentor
San Diego Astronomy Association
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International Dark-Sky Association
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