telescopecomparison · 2-way
Sky-Watcher Esprit 150ED vs William Optics Zenithstar 61 II
Sky-Watcher
Esprit 150ED
Best suited for intermediate imagers building a versatile kit running a permanent observatory setup.
William Optics
Zenithstar 61 II
Best suited for beginners and wide-field enthusiasts running a portable travel rig.
Key differences
+192% focal length
+146% aperture
Slower by 1.1 f-stops
Specifications
| Specification | Sky-Watcher Esprit 150ED | William Optics Zenithstar 61 II |
|---|---|---|
| Optics | ||
| Type | Refractor | refractor |
| Optical design | Triplet APO | Apo doublet FPL-53 |
| Aperture | 150mm | 61mm |
| Focal length | 1050mm | 360mm |
| Native f/ratio | f/7.0 | f/5.9 |
| Image circle | 44mm | 44mm |
| Full-frame support | Yes | No |
| Physical | ||
| Weight | 17.0kg | 1.9kg |
Advantages of Sky-Watcher Esprit 150ED
- Tighter framing — 1050mm vs 360mm focal length
- 146% more light-gathering aperture
Advantages of William Optics Zenithstar 61 II
- Wider field — 360mm vs 1050mm focal length
- Faster optics at f/5.9 vs f/7
- Lighter (1.9kg vs 17kg) — easier to travel with
Best for — Sky-Watcher Esprit 150ED
- Medium-sized galaxies and planetary nebulae
- Full-frame astro cameras and DSLRs
Best for — William Optics Zenithstar 61 II
- Large emission nebulae and star clusters
Sky-Watcher Esprit 150ED — typical FOV & scale
- With Full-frame (36×24mm, 3.76µm)FOV: 1.96° × 1.31°Scale: 0.74"/px
- With APS-C (23.5×15.7mm, 3.76µm)FOV: 1.28° × 0.86°Scale: 0.74"/px
- With IMX533 square (11.3×11.3mm, 3.76µm)FOV: 0.62° × 0.62°Scale: 0.74"/px
William Optics Zenithstar 61 II — typical FOV & scale
- With Full-frame (36×24mm, 3.76µm)FOV: 5.73° × 3.82°Scale: 2.15"/px
- With APS-C (23.5×15.7mm, 3.76µm)FOV: 3.74° × 2.50°Scale: 2.15"/px
- With IMX533 square (11.3×11.3mm, 3.76µm)FOV: 1.80° × 1.80°Scale: 2.15"/px
Sky-Watcher Esprit 150ED — recommended user
Best suited for intermediate imagers building a versatile kit running a permanent observatory setup.
William Optics Zenithstar 61 II — recommended user
Best suited for beginners and wide-field enthusiasts running a portable travel rig.