William Optics RedCat 51 WIFD compact Petzval astrograph (William Optics, SKU: L-RC51RDIII). William Optics RedCat 51 WIFD is a compact refractor designed for astrophotography. Its Petzval optical system includes an FPL-53 low-dispersion glass element to limit chromatic aberration and provide a corrected field without an additional flattener. The short tube makes it easier to build a portable imaging setup. The WIFD focuser, or William Optics Internal Focus Design, adjusts focus by moving elements inside the tube. It is compatible with an EAF drive, allowing the system to be expanded with automated focusing. The CNC-machined mounting rings feature a Vixen-type shoe for a finder or guide scope.
• optical design: Petzval with FPL-53 ED glass for wide-field astrophotography
• internal WIFD focuser compatible with an EAF drive
• corrected field without the need for an additional flattener
• compact tube with precision CNC-machined rings
• camera connection using the appropriate photographic adapter ring
• telescope: William Optics RedCat 51 WIFD
• mask for focusing: Bahtinov mask with mounting
• dew shield
• objective lens cap
• mounting rings
• dovetail plate: Vixen, measuring 210 mm in length
• soft carrying case
• documentation
• optical design: four-element Petzval
• objective diameter: 51 mm
• focal length: 250 mm
• focal ratio: f/4.9
• low-dispersion ED lens material: FPL-53 glass
• image circle diameter: 48 mm
• supported sensor formats: full frame, APS-C and Micro 4/3
• camera types: DSLRs, mirrorless cameras, CMOS cameras and CCD cameras
• camera systems using suitable M48 × 0.75 adapter rings: Canon EF, Canon RF, Nikon F, Nikon Z, Sony E, Pentax K, Micro 4/3 and Fuji X
• focuser: internal-focusing WIFD rack-and-pinion system
• focuser travel: 0–23 mm
• tube length: 298 mm
• tube weight: approximately 1.8 kg
• weight with mounting rings: approximately 2.4 kg
• tube colour: red
• manufacturer code: L-RC51RDIII
• warranty: 24 months
RedCat 51 WIFD combines Petzval optics with internal focusing in a compact astrophotography setup.
