Updated review to 5 stars
I originally gave this app 3 stars, mainly due to it not being completely intuitive to me in the beginning. But I’ve now used the app for a few years, and really feel it deserves 5 stars. With 9 telescopes and dozens of eyepieces (yes, I have a problem), I find the app indispensable during a viewing session. Once you input and save (archive) telescope, eyepiece, and observer details, just choose your scope/eyepiece combination, and the app gives you magnification, field of view, exit pupil, and several other pieces of useful information. The app is very helpful in comparing different combinations of equipment when figuring what you wish to use for observing. Give this app a shot, and you won’t be disappointed.
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A Very Utilitarian Application
The other reviewers are right; this is not all that intuitive in setup. Clear instructions are needed. However, this is a great app once you learn how to set it up. Spending the time to learn its idiosyncracies is well worth the trouble. All the optical train specifications are presented in one place for any telescope, eyepiece, and astronomer's eye. Very useful either at your desk or at the eyepiece. I recommend this application to anyone who has the patience to learn to use it.
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Difficult to use
I am a beginner and was looking for a calculator to help me understand the different eye pieces on my telescope. I was hoping that this app would pull the specs of my telescope and allow me to better understand the various lenses I have. I did not get much out of this app, I hope it gets improved significantly otherwise I would say don’t buy!
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