telescopecomparison · 2-way
William Optics FLT 120 vs Takahashi TSA-120
William Optics
FLT 120
Best suited for intermediate imagers building a versatile kit running a backyard imaging setup.
Takahashi
TSA-120
Best suited for intermediate imagers building a versatile kit running a backyard imaging setup.
Key differences
-13% focal length
Faster by 1.0 f-stops
Specifications
| Specification | William Optics FLT 120 | Takahashi TSA-120 |
|---|---|---|
| Optics | ||
| Type | Refractor | Refractor |
| Optical design | Triplet APO | Triplet APO |
| Aperture | 120mm | 120mm |
| Focal length | 780mm | 900mm |
| Native f/ratio | f/6.5 | f/7.5 |
| Image circle | 44mm | 44mm |
| Full-frame support | Yes | Yes |
| Physical | ||
| Weight | 7.7kg | 7.5kg |
Advantages of William Optics FLT 120
- Wider field — 780mm vs 900mm focal length
- Faster optics at f/6.5 vs f/7.5
Advantages of Takahashi TSA-120
- Tighter framing — 900mm vs 780mm focal length
Best for — William Optics FLT 120
- Medium-sized galaxies and planetary nebulae
- Full-frame astro cameras and DSLRs
Best for — Takahashi TSA-120
- Medium-sized galaxies and planetary nebulae
- Full-frame astro cameras and DSLRs
William Optics FLT 120 — typical FOV & scale
- With Full-frame (36×24mm, 3.76µm)FOV: 2.64° × 1.76°Scale: 0.99"/px
- With APS-C (23.5×15.7mm, 3.76µm)FOV: 1.73° × 1.15°Scale: 0.99"/px
- With IMX533 square (11.3×11.3mm, 3.76µm)FOV: 0.83° × 0.83°Scale: 0.99"/px
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
William Optics FLT 120 — recommended user
Best suited for intermediate imagers building a versatile kit running a backyard imaging setup.
Takahashi TSA-120 — recommended user
Best suited for intermediate imagers building a versatile kit running a backyard imaging setup.
