OTA · 2000–2017
Takahashi Sky-90
Key specifications
| Aperture | 90 mm |
|---|---|
| Focal length | 500 mm |
| Focal ratio | f/5.6 |
| Optical design | Fluorite Doublet |
About
90 mm f/5.6 air-spaced fluorite doublet, ~500 mm focal length, with a retractable dew shield in a compact tube. A portable widefield imaging/visual refractor; replaced in the imaging role by the FSQ-85ED.