Field Flatteners & Reducers

0.8x Focal Reducer & Field Flattener Optimized for GT71, GT81, Z81 & Z103 Refractors Illuminates Full-Frame Sensors Adjustable Back Focus ...

Reduces focal ratio to a fast f/3.9 0.7x reduction factor 44mm image circle fully illuminates full-frame sensors Standard 55mm back focus for easy...

Reduces focal length by a factor of 0.7x, changing the EdgeHD 800 from f/10 to f/7 4-element optical design maintains the native flat-field perfor...

Designed specifically for the William Optics ZenithStar 73 APO Delivers a 1.0x, perfectly flat field across full-frame sensors Connects to the Z73...

Corrects field curvature and coma for the Askar 103APO Maintains the native 700.4mm focal length and f/6.8 ratio Triplet optical design delivers s...

Converts the SharpStar 61EDPH to a fast f/4.5 astrograph Provides a 44mm image circle for full-frame sensor coverage Three-element air-spaced opti...

Dedicated Field Flattener for the William Optics FLT91 Telescope Corrects Field Curvature for Pinpoint Stars Edge-to-Edge Integrated Adjustment Ri...

1.0x Flattener Power Designed for William Optics Zenithstar 61 Full-Frame Sensor Coverage Adjustable Back Focus Mechanism M54 Telescope Thread &am...

Reduces EdgeHD 1100 focal ratio to f/7.7 5-element optical design with Lanthanum glass Increases field of view by 43% Maintains EdgeHD flat-field ...

Reduces telescope focal length by 37% Converts f/10 SCTs to f/6.3 and f/11 systems to f/7 Compatible with Celestron C5, C6, C8, C9.25, C11, and C1...

55mm back focus Works with f/5 to f/7 refractors Compatible with APS-C size cameras or smaller. Accepts 2" filters Optimized for refractors with...

0.7x Focal Reduction Factor 44mm Full-Frame Image Circle Maintains a Standard 55mm Backfocus 3-Element Air-Spaced Design with ED Glass Optimized f...

Reduces focal ratio by a factor of 0.7x for faster imaging 4-element design maintains the native flat-field performance of the EdgeHD 9.25" Provid...

0.7x Focal Reduction Factor Designed for ZWO FF107 & FF130 APO Refractors Triplet Optical Design with 1 ED Element Standard 55mm Back Focus In...

0.75x Reduction Factor Transforms Askar 71F to f/5.2 New Focal Length: 369mm Standard 55mm Back Focus Triplet Optical Design Description FAQ Sp...

Transforms Askar 103APO to an f/4.08, 420.24mm focal length system Quadruplet optical design provides field flattening for full-frame sensors Stan...

1.0x Flattener Power preserves native focal length Corrects field curvature for Full Frame sensors Designed for William Optics FLT132, GT102, and ...

Reduces Askar 120APO to a fast f/5.6 focal ratio Shortens focal length to 672mm for wider fields of view Triplet optical design provides field fla...

Designed specifically for the Askar 120APO Telescope 1x Magnification Factor Triplet Optical Design Maintains Native f/7 Focal Ratio Standard 55mm...

55mm back focus Works with f/5 to f/7 refractors Compatible with APS-C size cameras or smaller. Accepts 2" filters Optimized for refractors with...

Reduces 140APO Focal Ratio to f/5.6 Shortens 140APO Focal Length to 784mm Standard 55mm Back Focus Requirement Triplet Optical Design with Field F...

Starizona's SCT Corrector has been an incredibly popular focal reducer and coma corrector, giving astrophotographers with standard Schmidt-Cassegra...

Reduces FRA600 focal ratio to F/3.9 Designed for full-frame sensors Maintains a standard 55mm backfocus Features integrated M48 (2-inch) filter th...

Designed to fully illuminate full frame sensor on most APO refractors. The SharpStar 2.5" field flattener has a M69 male thread to connect the came...