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William Optics UltraCat Astrographs

William Optics UltraCat astrographs are Petzval refractors in the Cat series, built for fast, flat-field deep-sky imaging without a separate flattener. The UltraCat 56, 76 and 108 work at f/4.8 and use WIFD internal focusing.

The Ultra-Cat 131 at f/4.9 is the largest in the line, for more resolution on smaller galaxies and nebulae. The small apertures suit travel rigs, while the bigger ones need a sturdier equatorial or harmonic mount.

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$3,998.00 - $3,998.00
$3,998.00
$3,998.00 - $3,998.00
$3,998.00

William Optics UltraCat 108 f/4.8 WIFD

WO-T-C-108BR
1 in stock

108mm Aperture, 5-Element Advanced Petzval Optical Design Fast f/4.8 Focal Ratio with 518mm Focal Length Massive 60mm Flat-Field Image Circle Pate...

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$3,998.00 - $3,998.00
$3,998.00
$3,998.00 - $3,998.00
$3,998.00
$1,398.00 - $1,398.00
$1,398.00
$1,398.00 - $1,398.00
$1,398.00

William Optics UltraCat 56 f/4.8 WIFD

WO-T-C-56BR
6 in stock

56mm Aperture, 269mm Focal Length (f/4.8) 5-Element Advanced Petzval Optical Design 50mm Image Circle for Full-Frame Sensors William Optics Intern...

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$1,398.00 - $1,398.00
$1,398.00
$1,398.00 - $1,398.00
$1,398.00
William Optics Ultra-Cat 131 f/4.9 Petzval Astrograph
$5,398.00 - $5,398.00
$5,398.00
$5,398.00 - $5,398.00
$5,398.00

William Optics Ultra-Cat 131 f/4.9 Petzval Astrograph

WO-T-C-131BR

131mm Aperture 648mm Focal Length (f/4.9) 5-Element Advanced Petzval Optical Design 60mm Flat-Field Image Circle Patented WIFD Internal Focuser 13...

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$5,398.00 - $5,398.00
$5,398.00
$5,398.00 - $5,398.00
$5,398.00
$2,198.00 - $2,198.00
$2,198.00
$2,198.00 - $2,198.00
$2,198.00

William Optics UltraCat 76 f/4.8 WIFD

WO-T-C-76BR
2 in stock

76 mm Aperture, 365 mm Focal Length (f/4.8) 5-Element Advanced Petzval Optical Design 50 mm Corrected Image Circle William Optics Internal Focusin...

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$2,198.00 - $2,198.00
$2,198.00
$2,198.00 - $2,198.00
$2,198.00