The Sharpstar Full-Frame Flattener for the 61EDPH-III is a dedicated 1x field flattener with an air-spaced triplet design for superb correction.
This 3-element corrector delivers an illuminated and corrected field of 44mm, making the 61EDPH-III usable with full frame sensors. The working distance between the flattener and the sensor is 55mm. The flattener includes an M54 extension tube which can be removed in case extra backfocus is required. Without this, the resulting backfocus requirement becomes 81.5mm.
The 61EDPH-III 1x flattener can be connected to the focuser of the Sharpstar 61EDPH-III by using the M68 x 1 male thread. The camera side features the universal M48 x 0.75 male thread, allowing standard wide T-rings to be connected without the need for additional spacers. An internal M48 x 0.75 filter thread allows standard 2" filters to be used.