Astrophotoguru · Compare

telescopecomparison · 2-way

ZWO Seestar S50 vs William Optics RedCat 51

ZWO Seestar S50
ZWO

Seestar S50

Best suited for beginners and wide-field enthusiasts running a portable travel rig.

William Optics RedCat 51
William Optics

RedCat 51

Best suited for beginners and wide-field enthusiasts running a portable travel rig.

Specifications

SpecificationZWO Seestar S50William Optics RedCat 51
Optics
Typesmart-telescopeRefractor
Optical designApo triplet all-in-onePetzval APO
Aperture50mm51mm
Focal length250mm250mm
Native f/ratiof/5.0f/4.9
Image circle45mm
Full-frame supportNoYes
Physical
Weight2.5kg1.6kg
Advantages of ZWO Seestar S50

Closely matched on the compared specs.

Advantages of William Optics RedCat 51
  • Larger image circle (45mm) — supports bigger sensors
  • Lighter (1.6kg vs 2.5kg) — easier to travel with
Best for — ZWO Seestar S50
  • Wide-field nebulae and Milky Way regions
  • Fast imaging — short exposures per sub
Best for — William Optics RedCat 51
  • Wide-field nebulae and Milky Way regions
  • Fast imaging — short exposures per sub
  • Full-frame astro cameras and DSLRs
ZWO Seestar S50 — typical FOV & scale
  • With Full-frame (36×24mm, 3.76µm)
    FOV: 8.25° × 5.50°Scale: 3.10"/px
  • With APS-C (23.5×15.7mm, 3.76µm)
    FOV: 5.39° × 3.60°Scale: 3.10"/px
  • With IMX533 square (11.3×11.3mm, 3.76µm)
    FOV: 2.59° × 2.59°Scale: 3.10"/px
William Optics RedCat 51 — typical FOV & scale
  • With Full-frame (36×24mm, 3.76µm)
    FOV: 8.25° × 5.50°Scale: 3.10"/px
  • With APS-C (23.5×15.7mm, 3.76µm)
    FOV: 5.39° × 3.60°Scale: 3.10"/px
  • With IMX533 square (11.3×11.3mm, 3.76µm)
    FOV: 2.59° × 2.59°Scale: 3.10"/px
ZWO Seestar S50 — recommended user

Best suited for beginners and wide-field enthusiasts running a portable travel rig.

William Optics RedCat 51 — recommended user

Best suited for beginners and wide-field enthusiasts running a portable travel rig.

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