telescopecomparison · 2-way
William Optics FLT 120 vs Borg 107FL
William Optics
FLT 120
Best suited for intermediate imagers building a versatile kit running a backyard imaging setup.
Borg
107FL
Best suited for intermediate imagers building a versatile kit running a portable travel rig.
Key differences
+30% focal length
+12% aperture
Slower by 0.9 f-stops
Specifications
| Specification | William Optics FLT 120 | Borg 107FL |
|---|---|---|
| Optics | ||
| Type | Refractor | refractor |
| Optical design | Triplet APO | Apo doublet fluorite |
| Aperture | 120mm | 107mm |
| Focal length | 780mm | 600mm |
| Native f/ratio | f/6.5 | f/5.6 |
| Image circle | 44mm | — |
| Full-frame support | Yes | Yes |
| Physical | ||
| Weight | 7.7kg | 3.5kg |
Advantages of William Optics FLT 120
- Tighter framing — 780mm vs 600mm focal length
- 12% more light-gathering aperture
- Larger image circle (44mm) — supports bigger sensors
Advantages of Borg 107FL
- Wider field — 600mm vs 780mm focal length
- Faster optics at f/5.6 vs f/6.5
- Lighter (3.5kg vs 7.7kg) — easier to travel with
Best for — William Optics FLT 120
- Medium-sized galaxies and planetary nebulae
- Full-frame astro cameras and DSLRs
Best for — Borg 107FL
- Large emission nebulae and star clusters
- 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
Borg 107FL — typical FOV & scale
- With Full-frame (36×24mm, 3.76µm)FOV: 3.44° × 2.29°Scale: 1.29"/px
- With APS-C (23.5×15.7mm, 3.76µm)FOV: 2.24° × 1.50°Scale: 1.29"/px
- With IMX533 square (11.3×11.3mm, 3.76µm)FOV: 1.08° × 1.08°Scale: 1.29"/px
William Optics FLT 120 — recommended user
Best suited for intermediate imagers building a versatile kit running a backyard imaging setup.
Borg 107FL — recommended user
Best suited for intermediate imagers building a versatile kit running a portable travel rig.
