Coma-free field diameter (mm) = 0.022 * (f/D)³
Create optical pieces in the Hardware tab to quickly load their dimensions here.
Focal ratio: f/4.00
Coma-free field (linear): 1.408 mm
Coma-free field (apparent): 0.0672°
Coma-free in eyepiece: 8.1° of 82° AFOV
Coma-free field (surface): 0.97% of the eyepiece field area
Apparent diameter along the largest axis.
| Object | Apparent size | Across | Fits |
|---|---|---|---|
| Jupiter | 39.4″ | 6.14× | yes |
| M27 (Dumbbell) | 8.0′ | 0.50× | no |
| M13 (Hercules cluster) | 20.0′ | 0.20× | no |
| Moon | 31.1′ | 0.13× | no |
A project by Lucas Sifoni, Paul Faÿs from Gallifrey Optics, and Raphaël Labro from La3emedim.fr
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