Field of view of an eyepiece
Formula :
C '= Co / (F / f) * 60
C '= Field of view in minutes of arc
Co = Apparent field of the eyepiece in degrees
F = Focal length of telescope or telescope
f = focal length of the eyepiece
Here is an example :
Use of a 40 mm eyepiece offering an apparent field of 43o with a telescope with a focal length of 2 mm:
43 / (2000/40) * 60 = 51,6 ′ of arc
The eyepiece with this telescope will provide a field of view of 51,6 ′ of arc
CCD camera field of view
Formula :
S = 205 x P / FL
S = Field of view covered by one pixel in arc second
P = Physical dimension of a pixel in microns
FL = Telescope focal length
It remains to multiply by the number of pixels in width and height. To convert to minutes of arc divide by 60.
Richard Beauregard
Sky Astro - CCD
Revised 2022/06/04