Takahashi Epsilon-180ED — 180 mm f/2.8 hyperbolic flat-field astrograph The Epsilon-180ED is the fastest of Takahashi's Epsilon astrographs. A 180 mm hyperbolic primary and an integrated corrector deliver 500 mm at f/2.8 with a flat 44 mm image circle, which makes it a short-exposure, wide-field workhorse for nebulae and star fields.
Manufacturer model: Takahashi Epsilon-180ED · Specifications checked against manufacturer data on 2026-11-03
The Epsilon-180ED is the fastest of Takahashi's Epsilon astrographs. A 180 mm hyperbolic primary and an integrated corrector deliver 500 mm at f/2.8 with a flat 44 mm image circle, which makes it a short-exposure, wide-field workhorse for nebulae and star fields.
As in all Epsilon models, the hyperbolic primary corrects spherical aberration and coma, and a corrector integrated in the rack-and-pinion focuser flattens the field. Takahashi states that star images stay under 10 µm to the edge of the 44 mm image circle.
The 500 mm focal length gives a field of view of about 5°. The secondary mirror is held by a reinforced spider to avoid flexure. The focuser includes a Camera Angle Adjuster (CAA), so you can rotate the camera to frame your target. With the optional Epsilon Extender 1.5×, the system becomes 780 mm at f/4.3.
| Optical design | Hyperbolic flat-field astrograph: hyperbolic primary, flat secondary, field corrector |
|---|---|
| Effective aperture | 180 mm |
| Focal length | 500 mm |
| Focal ratio | f/2.8 |
| Image circle | 44 mm |
| Field of view | About 5° |
| Star size | Under 10 µm to the edge of the 44 mm image circle |
| With Epsilon Extender 1.5× (optional) | 780 mm, f/4.3 |
| Metal-back distance | 56.2 mm |
|---|---|
| Focuser | Rack-and-pinion with integrated corrector and Camera Angle Adjuster |
| Tube diameter | 232 mm |
| Tube length | 570 mm |
| Weight | 10.7 kg |
Takahashi Europe Epsilon-180ED · Takahashi 2025 catalogue
Epsilon-180ED. Metal back 56.2 mm. CAA included on focuser. Extender 1.5x optional (780 mm f/4.3). Takahashi Europe page text mistakenly says 'Epsilon-130D has a focal ratio of F/2.8'; 180ED figures used.
| Field of view (°) | 5 |
|---|---|
| Star size | Under 10 um to edge of 44 mm image circle |
| Metal back (mm) | 56.2 |
| Optional extender | Epsilon Extender 1.5x: 780 mm, f/4.3 |
Data sheet
Takahashi Epsilon-180ED — 180 mm f/2.8 hyperbolic flat-field astrograph The Epsilon-180ED is the fastest of Takahashi's Epsilon astrographs. A 180 mm hyperbolic primary and an integrated corrector deliver 500 mm at f/2.8 with a flat 44 mm image circle, which makes it a short-exposure, wide-field workhorse for nebulae and star fields.
Manufacturer model: Takahashi Epsilon-180ED · Specifications checked against manufacturer data on 2026-11-03
