telescope
William Optics
Ultra-Cat 56
56mm Petzval (5-element advanced) · 269mm f/4.8
Compact full-frame Petzval astrograph.
Check Current Price
Affiliate link. AstroPhotoGuru may earn a commission at no additional cost to you. Link for William Optics Ultra-Cat 56.
Product specifications can change. Please verify specifications and compatibility with the manufacturer or retailer before purchasing.
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 (5-element advanced) |
| Aperture | 56mm |
| Focal length | 269mm |
| Native f/ratio | f/4.8 |
| Image circle | 50mm |
| Full-frame support | Yes |
| Physical | |
| Weight | 2.6kg |
Typical FOV & image scale
With Full-frame (36×24mm, 3.76µm)
FOV 7.67° × 5.11°
Scale 2.88″/px
With APS-C (23.5×15.7mm, 3.76µm)
FOV 5.01° × 3.34°
Scale 2.88″/px
With IMX533 square (11.3×11.3mm, 3.76µm)
FOV 2.41° × 2.41°
Scale 2.88″/px
Typical targets
- M45 — PleiadesReflection Nebula · 110′Plan this target
- M44 — Beehive ClusterOpen Cluster · 95′Plan this target
- NGC 7000 — North America NebulaEmission Nebula · 120′Plan this target
- IC 2177 — Seagull NebulaEmission Nebula · 120′Plan this target
- M8 — Lagoon NebulaEmission Nebula · 90′Plan this target
- M24 — Sagittarius Star CloudOpen Cluster · 90′Plan this target
Recommended cameras
Compare with similar
Source: williamoptics.com