Optec TCF-S - 2" Crayford focuser with temperature compensation

OPTEC TCF-S - 2" focuser with temperature compensation

Motorized focuser for high instrument load

The TCF-S is a robust Crayford focuser with very precise components, no radial play and a backlash of just 0.03 mm, making it ideal for photographic applications. The TCF-S also has a temperature sensor that transmits temperature changes to the controller and can therefore correct the focus position based on temperature changes.

Motor drive with high resolution

A stepper motor with gearbox provides a position resolution of 2.1 µm. The focuser requires 89 mm intrafocal travel from the end of the drawtube (measured in center position). The travel is 15.2 mm in 7000 steps.

Operation via PC or manual control

The focuser is operated with two push buttons on the hand control box. A digital display shows the current position.

Integrated automatic temperature compensation

A major advantage of this system is the ability to compensate for temperature-related focus drift. With an SC telescope, for example, this can be up to 0.25 mm per Kelvin temperature change.
As a result, the focus position changes noticeably and blurring over the course of the exposure time would be the inevitable consequence. Long exposures would therefore not be possible. The TCF-S masters this problem and guarantees sharp images even with large temperature differences during the exposure time!

Software and drivers

The current versions of the required drivers and software can be found on the manufacturer website.