telescope
William Optics
RedCat 71
71mm Petzval APO · 350mm f/4.9
Petzval astrograph; native full-frame.
Best for
- Wide-field nebulae and Milky Way regions
- Fast imaging — short exposures per sub
- Full-frame astro cameras and DSLRs
Specifications
| Optics | |
| Type | Refractor |
| Optical design | Petzval APO |
| Aperture | 71mm |
| Focal length | 350mm |
| Native f/ratio | f/4.9 |
| Image circle | 45mm |
| Full-frame support | Yes |
| Physical | |
| Weight | 2.7kg |
Typical FOV & image 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
Recommended accessories
- Tele Vue Powermate 2xfocal_extender · 2× focal lengthunknown
- William Optics Flat 6AIIIflattener · 1× focal lengthcommunity reported
Typical targets
- IC IC 5070 — Pelican NebulaEmission Nebula · 80′
- NGC NGC 2237 — Rosette NebulaEmission Nebula · 80′
- Messier M7 — Ptolemy's ClusterOpen Cluster · 80′
- Messier M42 — Orion NebulaEmission Nebula · 85′
- IC IC 2944 — Running Chicken NebulaEmission Nebula · 75′
- Messier M33 — Triangulum GalaxyGalaxy · 73′
Recommended cameras
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Compare pairing28.3mm sensor · 3.76µm px · cooled
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