CALCULATION OF THE FIELD OF VIEW OF AN EYEPIECE OR AN ASTRONOMIC CAMERA

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