TS-Optics NEWTON Coma Corrector 0.85x Reducer - big Sensors - 3" connection

TS-Optics 3" Newtonian Coma Corrector and 0.85x Focal Reducer

Teleskop-Service has developed the Newtonian coma corrector and now offers reduction of the focal length and with increasing the speed. The focal ratio of an f/4 Newtonians is improved to f/3.4. At the same time, coma is fully corrected.

The corrector can be used with all Newtonian telescopes with 3" focuser. It can be clamped directly via a 3" receptacle or threaded via the M82x1 thread. We recommend the corrector for all Newtonian telescopes of at least 10" aperture.

The usable field of the TS 0.85x coma corrector:

The corrector illuminates up to 46 mm with 100% with very good correction at the same time. A sufficiently large secondary mirror is required, of course. With this, you can use cameras with sensors up to full-frame size. We recommend to always use a star at the outer third of the field of view for focusing, thus you achieve a very good sharpness over the entire field.

Adaption of the camera to the TS 0.85x coma corrector:

At the camera side, the corrector provides three threads for camera adaption.

♦ M76x1 thread (male): this thread is already in use for the connection adapter for the threaded joint.
♦ M68x1 thread (female): working distance to the optimal sensor position is 61 mm
♦ M54x0.75 thread (female): working distance to the optimal sensor position is 55 mm

Adaption recommendation to M48x0.75 with 55 mm working distance - perfect for DSLR and astro cameras:

The TSM68-M48 adapter is specially designed for this corrector. It builds up 6 mm, so you achieve exactly 55 mm working distance from the M48 thread. In addition, the adapter offers a 2" female thread for the adaptation of 2" filters. The adapter is used instead of the M54 female thread adapter on the corrector.

♦ TS 0.85 Newtonian corrector
♦ Metal dust caps

Question:
How do you have to measure the working distance

Answer from Teleskop-Service:
The working distance is measured from the beginning of the connection thread on the housing of the corrector (see example picture):