telescopecomparison · 2-way
William Optics Zenithstar 61 II vs William Optics RedCat 61

William Optics
Zenithstar 61 II
Best suited for beginners and wide-field enthusiasts running a portable travel rig.

William Optics
RedCat 61
Best suited for beginners and wide-field enthusiasts running a portable travel rig.
Key differences
+20% focal length
Slower by 1.0 f-stops
Specifications
| Specification | William Optics Zenithstar 61 II | William Optics RedCat 61 |
|---|---|---|
| Optics | ||
| Type | refractor | Refractor |
| Optical design | Apo doublet FPL-53 | Petzval APO |
| Aperture | 61mm | 61mm |
| Focal length | 360mm | 300mm |
| Native f/ratio | f/5.9 | f/4.9 |
| Image circle | 44mm | 45mm |
| Full-frame support | No | Yes |
| Physical | ||
| Weight | 1.9kg | 2.0kg |
Advantages of William Optics Zenithstar 61 II
- Tighter framing — 360mm vs 300mm focal length
Advantages of William Optics RedCat 61
- Wider field — 300mm vs 360mm focal length
- Faster optics at f/4.9 vs f/5.9
Best for — William Optics Zenithstar 61 II
- Large emission nebulae and star clusters
Best for — William Optics RedCat 61
- Wide-field nebulae and Milky Way regions
- Fast imaging — short exposures per sub
- Full-frame astro cameras and DSLRs
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
William Optics RedCat 61 — typical FOV & scale
- With Full-frame (36×24mm, 3.76µm)FOV: 6.88° × 4.58°Scale: 2.59"/px
- With APS-C (23.5×15.7mm, 3.76µm)FOV: 4.49° × 3.00°Scale: 2.59"/px
- With IMX533 square (11.3×11.3mm, 3.76µm)FOV: 2.16° × 2.16°Scale: 2.59"/px
William Optics Zenithstar 61 II — recommended user
Best suited for beginners and wide-field enthusiasts running a portable travel rig.
William Optics RedCat 61 — recommended user
Best suited for beginners and wide-field enthusiasts running a portable travel rig.