Equipment
增倍镜
Barlow lens
A lens before the eyepiece that doubles the effective focal length.
A 2× Barlow dims the image fourfold.
Related terms
- Exposure — How long a camera sensor collects light.
- Tracking — Moving the gear with the sky so stars stay round.
- Collimation — Aligning a reflector's mirrors.
- Cool-down — A scope reaching ambient temperature.