HAS Telescope Calculator


As a minimum you will need to fill in the aperture. To do any calculations on eyepieces you must also fill in the focal ratio or length. The total number of results will vary according to the amount of information you provide.

Aperture mm or inch
Focal ratio f/ or length mm
Eyepiece mm
Apparent field degrees
Barlow lens times
CCD width mm times height mm
CCD width pixels


Copyright: Maarten de Vries ©2011