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telescopecomparison · 2-way

William Optics Ultra-Cat 131 vs Tele Vue NP127fli

William Optics Ultra-Cat 131
William Optics

Ultra-Cat 131

Best suited for intermediate imagers building a versatile kit running a backyard imaging setup.

Tele Vue NP127fli
Tele Vue

NP127fli

Best suited for intermediate imagers building a versatile kit running a backyard imaging setup.

Specifications

SpecificationWilliam Optics Ultra-Cat 131Tele Vue NP127fli
Optics
Typerefractorrefractor
Optical designPetzval (5-element advanced)Nagler-Petzval
Aperture131mm127mm
Focal length648mm660mm
Native f/ratiof/4.9f/5.2
Image circle60mm52mm
Full-frame supportYesYes
Physical
Weight11.3kg9.5kg
Advantages of William Optics Ultra-Cat 131
  • Larger image circle (60mm) — supports bigger sensors
Advantages of Tele Vue NP127fli
  • Lighter (9.5kg vs 11.3kg) — easier to travel with
Best for — William Optics Ultra-Cat 131
  • Large emission nebulae and star clusters
  • Fast imaging — short exposures per sub
  • Full-frame astro cameras and DSLRs
Best for — Tele Vue NP127fli
  • Large emission nebulae and star clusters
  • Full-frame astro cameras and DSLRs
William Optics Ultra-Cat 131 — typical FOV & scale
  • With Full-frame (36×24mm, 3.76µm)
    FOV: 3.18° × 2.12°Scale: 1.20"/px
  • With APS-C (23.5×15.7mm, 3.76µm)
    FOV: 2.08° × 1.39°Scale: 1.20"/px
  • With IMX533 square (11.3×11.3mm, 3.76µm)
    FOV: 1.00° × 1.00°Scale: 1.20"/px
Tele Vue NP127fli — typical FOV & scale
  • With Full-frame (36×24mm, 3.76µm)
    FOV: 3.13° × 2.08°Scale: 1.18"/px
  • With APS-C (23.5×15.7mm, 3.76µm)
    FOV: 2.04° × 1.36°Scale: 1.18"/px
  • With IMX533 square (11.3×11.3mm, 3.76µm)
    FOV: 0.98° × 0.98°Scale: 1.18"/px
William Optics Ultra-Cat 131 — recommended user

Best suited for intermediate imagers building a versatile kit running a backyard imaging setup.

Tele Vue NP127fli — recommended user

Best suited for intermediate imagers building a versatile kit running a backyard imaging setup.

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