O P T I C C L A S S
Size
Small
Medium
Large
Giant
Binocular - mm
< 50
50-80
80-100
>100
Telescope - "
Refractor
< 4
4-6
6-10
> 10
Reflector
< 8
8-12
12-25
> 25
Field of View
Binocular
< 5
5 - 6
6 - 7
> 7
Telescope
< 3
3 - 4
4 - 5
> 5