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Upcoming Stargazing September 16th
Upcoming Stargazing September 16th

William Optics RedCat 51 APO 250mm f/4.9

SKU L-RC51Ix-1

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Interchangeable Camera mount
Full Frame / APS-C Compatible
World's Sharpest 250mm
Apochromatic FPL-53 Lens
Super Bright Bahtinov Mask
Dual Spec Mounting Base
Field Rotator for framing
Small and easy to store
48mm Filter slot in the adapter
Modular Mounting Options
Invertible Sun Shade/Dew Shield


Lens Type: Prime Lens
Focal Length: 250mm
Diameter: 51mm
Aperture: f/4.9
Camera Format: APS-C, Full Frame
Image Circle: > Full Frame
Focus Mode: Manus Focus
Lens Structure: Petzval (4 Elements in 3 Groups)
Dimensions: 225mm x 80mm x 80mm
Tube Length: 305mm Outward / 225mm Inward
Weight: 1.8 kg (4 lbs)