telescopecomparison · 2-way
William Optics Pleiades 181 vs William Optics FLT 156
William Optics
Pleiades 181
Best suited for intermediate imagers building a versatile kit running a permanent observatory setup.
William Optics
FLT 156
Best suited for intermediate imagers building a versatile kit running a backyard imaging setup.
Key differences
-8% focal length
+16% aperture
Faster by 1.5 f-stops
Specifications
| Specification | William Optics Pleiades 181 | William Optics FLT 156 |
|---|---|---|
| Optics | ||
| Type | astrograph | refractor |
| Optical design | Astrograph (7-element) | Apo triplet FPL-53 |
| Aperture | 181mm | 156mm |
| Focal length | 998mm | 1085mm |
| Native f/ratio | f/5.5 | f/7.0 |
| Image circle | 55mm | 52mm |
| Full-frame support | Yes | Yes |
| Physical | ||
| Weight | 15.0kg | 11.5kg |
Advantages of William Optics Pleiades 181
- 16% more light-gathering aperture
- Faster optics at f/5.5 vs f/7
Advantages of William Optics FLT 156
- Lighter (11.5kg vs 15kg) — easier to travel with
Best for — William Optics Pleiades 181
- Medium-sized galaxies and planetary nebulae
- Full-frame astro cameras and DSLRs
Best for — William Optics FLT 156
- Medium-sized galaxies and planetary nebulae
- Full-frame astro cameras and DSLRs
William Optics Pleiades 181 — typical FOV & scale
- With Full-frame (36×24mm, 3.76µm)FOV: 2.07° × 1.38°Scale: 0.78"/px
- With APS-C (23.5×15.7mm, 3.76µm)FOV: 1.35° × 0.90°Scale: 0.78"/px
- With IMX533 square (11.3×11.3mm, 3.76µm)FOV: 0.65° × 0.65°Scale: 0.78"/px
William Optics FLT 156 — typical FOV & scale
- With Full-frame (36×24mm, 3.76µm)FOV: 1.90° × 1.27°Scale: 0.71"/px
- With APS-C (23.5×15.7mm, 3.76µm)FOV: 1.24° × 0.83°Scale: 0.71"/px
- With IMX533 square (11.3×11.3mm, 3.76µm)FOV: 0.60° × 0.60°Scale: 0.71"/px
William Optics Pleiades 181 — recommended user
Best suited for intermediate imagers building a versatile kit running a permanent observatory setup.
William Optics FLT 156 — recommended user
Best suited for intermediate imagers building a versatile kit running a backyard imaging setup.
