Choose telescope type and aperture. See how different objects appear through the eyepiece.
Eyepiece View
Light Gathering Comparison
Airy Disk / Resolution
Telescope Type
Target Object
Specifications
40x
Magnification
1.25
FOV (degrees)
0.58"
Resolution
1x
Light Gathering
Rayleigh Criterion: Angular resolution = 1.22 * wavelength / aperture. Light Gathering: Proportional to aperture squared. A 200mm scope gathers 816x more light than your eye (7mm pupil). Max Useful Mag: ~2x aperture in mm.