There’s a new observing app for the iPhone, iPod and iPad, called TeleCalc. Enter in two data points about your telescope (aperture and focal ratio) and two about the eyepiece (focal length and diameter) the program calculates angular field of view, best eyepiece magnification, resolution (Dawes, Rayleight), exit pupil, limiting stellar magnitude and light gathering power.
TeleCalc is available in eight languages: English, Spanish, French, Italian, German, Portuguese, Russian and Japanese. Search “TeleCalc” in iTunes to download it or find it on the iTunes store.
Thanks to developer Fabio Rendelucci who has given Universe Today 3 free TeleCalc apps to give away.
The first 3 people to answer the following question will be sent a code for a free TeleCalc app:
To find the magnifying power of any telescope, divide the focal length of the telescope by the focal length of the what other telescope piece?
Submit your answers in the “Comments”