Will It Fit? A Discussion of True Field Of View

This video is the twelfth video in the Old Gazer series, which seeks to provide practical guidance and inspiration for beginning or inexperienced amateur astronomers.

This video discusses true field of view. It reveals what true field of view is and why it is important when viewing night sky objects in a telescope. The significance of magnification and the apparent field of view of eyepieces is discussed and a formula is given by which true field of view may be calculated - with several examples given.

The overall concept of the celestial sphere is discussed in relation to the size of objects in the night sky, which are usually measured in degrees, arc minutes, or arc seconds.

A resource is suggested for finding the angular size of Messier Objects in the night sky. That resource may be found here:
starlust.org/messier-catalog/

Two resources are suggested for visual determinations of field of view for both visual and imaging applications, with examples given for each resource. Those resources may be found here:
stellarium.org
astronomy.tools

The value of calculating true field of view for given telescope/eyepiece combinations is emphasized, particularly with regard to viewing night sky objects with a large angular size.

Music in this video is "So My Love - Instrumental Version", by Anthem of Rain. Contact the artist here:
https://freemusicarchive.org/music/an...