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

Features

• Connection at telescope side: 3" barrel and M82x1 thread (male)
• Connection at camera side: M68x1 thread (female) and M54x0.75 thread (female)
• Working distance: 61 mm from the M68 thread and 55 mm from the M54 thread
• Length of corrector: 107 mm without the thread adapters at camera side
• Number of elements: 4 elements
• Coating: Antireflective multi-coating
• Full illumination and field correction up to 46 mm diameter (full-frame size)
• Reduces the focal length to 85% and thus shortens the exposure times to less than 75%
• Can be screwed to the focuser via the male M82x1 thread of the corrector
• The corrector needs a focus position of 190 mm above the tube or 90 mm above the 3" receptacle of the focuser