Equipment
出瞳直径
Exit pupil
Aperture divided by magnification.
Past 7 mm the light is wasted — your pupil cannot open that far.
Related terms
- Tripod — The base holding a telescope or camera.
- Binoculars — Two short scopes side by side: wide field, easy to aim.
- Exposure — How long a camera sensor collects light.
- Tracking — Moving the gear with the sky so stars stay round.