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Eyepiece Selector by pupil size, free software. For Sale

Price - n/a

Ad Number: 127663

Posted: 30 Jan 2018

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I have a program that I wrote that provides information about which eyepieces will work well with your eyes. It calculates based on your pupil size how much light is lost from a given telescope/eyepiece combination. Currently its database holds 294 eyepieces of various brands, and I am willing to add others if I can get the information.
I have versions for windows and Linux, and if I can find someone out there with a Mac and a current copy of purebasic, he could compile us a copy for Macs (purebasic runs and compiles under all 3 systems).
I can email a zipped version for Windows (most emails won't accept executable files as they could be viruses) or the linux version free of charge. Send a request to johnduchek@gmail.com and I will send a copy (Windows, Linux, or both) by return email. I have attached a screenshot. If you want more info on pupil size, I can attach an article on that also.

One simple way to measure your pupil size in the dark is to stand in front of a mirror with a mm ruler taped to it in a dark room and snap a flash picture with your phone. According to what I have heard (haven't tried it) you can measure your pupil size as it doesn't change fast with the flash. I was corrected on this by a reader. The ruler has to be held up under your eye so that the scale is correct. You can tell I haven't tried it myself. ;-)

Fast scopes in particular can limit which eyepieces work as you get older. They effectively make the aperture smaller as the light cone is too big for your pupil size. This can help you see which size eyepieces will work best for you.



  • Condition New
  • Location Saint Louis

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