telescopecomparison · 2-way
William Optics FLT 132 vs Borg 90FL
William Optics
FLT 132
Best suited for intermediate imagers building a versatile kit running a backyard imaging setup.
Key differences
+85% focal length
+47% aperture
Slower by 1.4 f-stops
Specifications
| Specification | William Optics FLT 132 | Borg 90FL |
|---|---|---|
| Optics | ||
| Type | refractor | refractor |
| Optical design | Apo triplet FPL-53 | Apo doublet fluorite |
| Aperture | 132mm | 90mm |
| Focal length | 925mm | 500mm |
| Native f/ratio | f/7.0 | f/5.6 |
| Image circle | 52mm | — |
| Full-frame support | Yes | No |
| Physical | ||
| Weight | 7.9kg | 2.5kg |
Advantages of William Optics FLT 132
- Tighter framing — 925mm vs 500mm focal length
- 47% more light-gathering aperture
- Larger image circle (52mm) — supports bigger sensors
Advantages of Borg 90FL
- Wider field — 500mm vs 925mm focal length
- Faster optics at f/5.6 vs f/7
- Lighter (2.5kg vs 7.9kg) — easier to travel with
Best for — William Optics FLT 132
- Medium-sized galaxies and planetary nebulae
- Full-frame astro cameras and DSLRs
Best for — Borg 90FL
- Large emission nebulae and star clusters
William Optics FLT 132 — typical FOV & scale
- With Full-frame (36×24mm, 3.76µm)FOV: 2.23° × 1.49°Scale: 0.84"/px
- With APS-C (23.5×15.7mm, 3.76µm)FOV: 1.46° × 0.97°Scale: 0.84"/px
- With IMX533 square (11.3×11.3mm, 3.76µm)FOV: 0.70° × 0.70°Scale: 0.84"/px
Borg 90FL — 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
William Optics FLT 132 — recommended user
Best suited for intermediate imagers building a versatile kit running a backyard imaging setup.
Borg 90FL — recommended user
Best suited for beginners and wide-field enthusiasts running a portable travel rig.