telescopecomparison · 2-way
William Optics Zenithstar 73 II vs Explore Scientific ED80 FCD-100
William Optics
Zenithstar 73 II
Best suited for beginners and wide-field enthusiasts running a portable travel rig.
Explore Scientific
ED80 FCD-100
Best suited for beginners and wide-field enthusiasts running a portable travel rig.
Key differences
-10% focal length
-9% aperture
Specifications
| Specification | William Optics Zenithstar 73 II | Explore Scientific ED80 FCD-100 |
|---|---|---|
| Optics | ||
| Type | refractor | refractor |
| Optical design | Apo doublet FPL-53 | Apo triplet FCD-100 |
| Aperture | 73mm | 80mm |
| Focal length | 430mm | 480mm |
| Native f/ratio | f/5.9 | f/6.0 |
| Image circle | 44mm | 44mm |
| Full-frame support | No | No |
| Physical | ||
| Weight | 2.4kg | 4.5kg |
Advantages of William Optics Zenithstar 73 II
- Wider field — 430mm vs 480mm focal length
- Lighter (2.4kg vs 4.5kg) — easier to travel with
Advantages of Explore Scientific ED80 FCD-100
- Tighter framing — 480mm vs 430mm focal length
Best for — William Optics Zenithstar 73 II
- Large emission nebulae and star clusters
Best for — Explore Scientific ED80 FCD-100
- Large emission nebulae and star clusters
William Optics Zenithstar 73 II — typical FOV & scale
- With Full-frame (36×24mm, 3.76µm)FOV: 4.80° × 3.20°Scale: 1.80"/px
- With APS-C (23.5×15.7mm, 3.76µm)FOV: 3.13° × 2.09°Scale: 1.80"/px
- With IMX533 square (11.3×11.3mm, 3.76µm)FOV: 1.51° × 1.51°Scale: 1.80"/px
Explore Scientific ED80 FCD-100 — typical FOV & scale
- With Full-frame (36×24mm, 3.76µm)FOV: 4.30° × 2.86°Scale: 1.62"/px
- With APS-C (23.5×15.7mm, 3.76µm)FOV: 2.81° × 1.87°Scale: 1.62"/px
- With IMX533 square (11.3×11.3mm, 3.76µm)FOV: 1.35° × 1.35°Scale: 1.62"/px
William Optics Zenithstar 73 II — recommended user
Best suited for beginners and wide-field enthusiasts running a portable travel rig.
Explore Scientific ED80 FCD-100 — recommended user
Best suited for beginners and wide-field enthusiasts running a portable travel rig.