telescopecomparison · 2-way
Takahashi TSA-120 vs Takahashi Epsilon-180ED
Takahashi
TSA-120
Best suited for intermediate imagers building a versatile kit running a backyard imaging setup.
Takahashi
Epsilon-180ED
Best suited for beginners and wide-field enthusiasts running a permanent observatory setup.
Key differences
+80% focal length
-33% aperture
Slower by 4.7 f-stops
Specifications
| Specification | Takahashi TSA-120 | Takahashi Epsilon-180ED |
|---|---|---|
| Optics | ||
| Type | Refractor | astrograph |
| Optical design | Triplet APO | Hyperbolic Newtonian |
| Aperture | 120mm | 180mm |
| Focal length | 900mm | 500mm |
| Native f/ratio | f/7.5 | f/2.8 |
| Image circle | 44mm | 44mm |
| Full-frame support | Yes | Yes |
| Physical | ||
| Weight | 7.5kg | 12.5kg |
Advantages of Takahashi TSA-120
- Tighter framing — 900mm vs 500mm focal length
- Lighter (7.5kg vs 12.5kg) — easier to travel with
Advantages of Takahashi Epsilon-180ED
- Wider field — 500mm vs 900mm focal length
- 50% more light-gathering aperture
- Faster optics at f/2.8 vs f/7.5
Best for — Takahashi TSA-120
- Medium-sized galaxies and planetary nebulae
- Full-frame astro cameras and DSLRs
Best for — Takahashi Epsilon-180ED
- Large emission nebulae and star clusters
- Fast imaging — short exposures per sub
- Full-frame astro cameras and DSLRs
Takahashi TSA-120 — typical FOV & scale
- With Full-frame (36×24mm, 3.76µm)FOV: 2.29° × 1.53°Scale: 0.86"/px
- With APS-C (23.5×15.7mm, 3.76µm)FOV: 1.50° × 1.00°Scale: 0.86"/px
- With IMX533 square (11.3×11.3mm, 3.76µm)FOV: 0.72° × 0.72°Scale: 0.86"/px
Takahashi Epsilon-180ED — typical FOV & scale
- With Full-frame (36×24mm, 3.76µm)FOV: 4.13° × 2.75°Scale: 1.55"/px
- With APS-C (23.5×15.7mm, 3.76µm)FOV: 2.69° × 1.80°Scale: 1.55"/px
- With IMX533 square (11.3×11.3mm, 3.76µm)FOV: 1.29° × 1.29°Scale: 1.55"/px
Takahashi TSA-120 — recommended user
Best suited for intermediate imagers building a versatile kit running a backyard imaging setup.
Takahashi Epsilon-180ED — recommended user
Best suited for beginners and wide-field enthusiasts running a permanent observatory setup.