William Optics Reducer / Adjustable Field Flattener

This unit is specifically engineered for the GT153, FLT 132, 102GTS, and GT102 refractor models. It is not a universal accessory, so ensure your specific telescope model is listed before purchasing.

Yes, it is designed to support full-frame DSLR and mirrorless cameras. It provides a 45mm imaging circle, which ensures coverage across the entire sensor without significant vignetting.

Adjustable back focus allows you to fine-tune the distance between the flattener and your camera sensor. This precision is critical for achieving perfectly round stars across the entire frame, especially when using different camera bodies or filter wheels.

The 0.72x factor reduces your telescope's effective focal length, which effectively widens your field of view and increases the speed of your optical system. This allows for shorter exposure times and captures larger deep-sky objects in a single frame.

The triplet ED (Extra-low Dispersion) design is used to minimize chromatic aberration, which is the color fringing often seen around bright stars. By using high-quality Ohara optical glass, this design ensures superior color correction and sharpness.

No, the internal surfaces are blackened to suppress stray light and reflections. Combined with the STM coatings on the lens elements, this design helps maintain high contrast and clarity in your final images.