William Optics Flat6A III Reducer Flattener Adjustable 50.8 mm

William Optics Flat6A III Adjustable 50.8 mm Reducer Flattener: WO's most versatile flattener-reducer

The William Optics Flat6AIII combines a field flattener with a 0.8x reducer. Every refractor naturally produces a slightly curved image plane; a flat camera sensor cuts through it, causing stars in the corners to stretch into streaks. A flattener corrects that curvature, keeping stars small and round all the way to the corners. The reducer also shortens the focal length: a wider field of view and shorter exposures.

The correction is calculated up to full-frame and works across virtually the entire field on APS-C. Made for the William Optics GT71, GT81, Z81, and Z103, and more broadly applicable to f/6 to f/7.5 refractors.

Adjustable with scale

Using the distance scale adjustment, you tune the flattener to your telescope and camera; you can easily set the value you found again for the next session. The black-coated interior suppresses reflections.

On the train

Telescope side M63, camera side M48 with 48 mm filter thread. With the William Optics M48 adapter for your bayonet, the sensor is directly at the correct distance; the separate M63 adapter with 2-inch barrel allows mounting in a 2-inch focuser.

Featured accessories

Combine the Flat6AIII with the M48 adapter for your cameramerk and, if you have a 2-inch focuser, with the M63/2-inch adapter.

For whom yes and for whom no

• ✓ Owners of a GT71, GT81, Z81 or Z103 who take photos
• ✓ Owners of other f/6 to f/7.5 refractors who want to gain field and speed
• ✗ Owners of faster optics (f/5): look instead at the Flat7A

Specifications

You can find more accessories for this merk at the William Optics merk Page.