telescopecomparison · 2-way
William Optics RedCat 71 vs SharpStar 61EDPH III
William Optics
RedCat 71
Best suited for beginners and wide-field enthusiasts running a portable travel rig.
SharpStar
61EDPH III
Best suited for beginners and wide-field enthusiasts running a portable travel rig.
Key differences
+16% aperture
Faster by 0.6 f-stops
Specifications
| Specification | William Optics RedCat 71 | SharpStar 61EDPH III |
|---|---|---|
| Optics | ||
| Type | Refractor | Refractor |
| Optical design | Petzval APO | Doublet APO |
| Aperture | 71mm | 61mm |
| Focal length | 350mm | 335mm |
| Native f/ratio | f/4.9 | f/5.5 |
| Image circle | 45mm | 32mm |
| Full-frame support | Yes | No |
| Physical | ||
| Weight | 2.7kg | 2.4kg |
Advantages of William Optics RedCat 71
- 16% more light-gathering aperture
- Faster optics at f/4.9 vs f/5.5
- Larger image circle (45mm) — supports bigger sensors
Advantages of SharpStar 61EDPH III
Closely matched on the compared specs.
Best for — William Optics RedCat 71
- Wide-field nebulae and Milky Way regions
- Fast imaging — short exposures per sub
- Full-frame astro cameras and DSLRs
Best for — SharpStar 61EDPH III
- Wide-field nebulae and Milky Way regions
William Optics RedCat 71 — typical FOV & scale
- With Full-frame (36×24mm, 3.76µm)FOV: 5.89° × 3.93°Scale: 2.22"/px
- With APS-C (23.5×15.7mm, 3.76µm)FOV: 3.85° × 2.57°Scale: 2.22"/px
- With IMX533 square (11.3×11.3mm, 3.76µm)FOV: 1.85° × 1.85°Scale: 2.22"/px
SharpStar 61EDPH III — typical FOV & scale
- With Full-frame (36×24mm, 3.76µm)FOV: 6.16° × 4.11°Scale: 2.32"/px
- With APS-C (23.5×15.7mm, 3.76µm)FOV: 4.02° × 2.69°Scale: 2.32"/px
- With IMX533 square (11.3×11.3mm, 3.76µm)FOV: 1.93° × 1.93°Scale: 2.32"/px
William Optics RedCat 71 — recommended user
Best suited for beginners and wide-field enthusiasts running a portable travel rig.
SharpStar 61EDPH III — recommended user
Best suited for beginners and wide-field enthusiasts running a portable travel rig.