TCF Focuser Series
TCF - Temperature Compensating Focusers
Back
in 1999 Optec's Gerald Persha designed and introduced the first
all-digital motorized telescope focuser. Featuring a closed-loop
design with external hand control box and built-in temperature
compensation, that very first TCF Temperature Compensating
Focuser continues to operate every clear night at the Optec
Observatory. Utilizing a best-fit linear model to correct for
temperature induced focal shifts, the TCF performs superbly without
requiring a re-focus of the telescope for weeks at a time.
As
the first few focusers rolled out to customers, we quickly saw the need
for PC computer control. By adding a serial UART chip and ASCII command
set to the control circuit, the TCF-S was born.
Now
focus control, along with serial "go-to" telescope mounts and imaging cameras
could be controlled by a host of software packages.
The remotely
controlled observatory became a reality for many amateurs and small
colleges using off-the-shelf products. The revolutionary TCF-S was
awarded a Sky & Telescope Hot Product award in 2000 for
its contribution to this dramatic change in the way astronomy research
and imaging was being accomplished.
Since that time the TCF Focuser Series
has grown to include larger focusers, focusers with integrated
electronics, and new more durable controllers such as the
FocusLynx which expands the serial protocols to include USB,
Ethernet, and wireless WiFi capablity. Optec engineers continue
the innovation with linear encoder versions for sub-micron positional
accuracy. Throughout all this growth,
Optec has continually acheived the overarching goal of robust mechanical
design with intelligent electronics for remote observatory operations.
TCF Focuser 2-inch Models
Original TCF-S Temperature Compensating Focuser

The original TCF-S Temperature Compensating Focuser is still available with many improvements made over the years. Now with a fifth generation serial control circuit, the TCF-S continues to be a highly sought after all-digital premium focuser.
With 2.2 micron steps and over 15mm of travel, the TCF-S provides excellent resolution and plenty of focus travel for computer auto-focusing. Naturally, temperature compensation is built in and the external control box allows manual and closed-loop control as well as PC and Mac computer control. Fully ASCOM compliant, the TCF-S remains the most robust 2-inch digital focuser available. Click here for full details or to order the TCF-S Temperature Compensating Focuser.
TCF-Si Integrated Temperature Compensating Focuser
Both varieties of TCF-S focuser are also available with a control
system that is integrated into the focuser. This allows users to have
direct computer control of their focuser and eliminates the need for an
external control box and control cable, thus making this variant an
excellent choice for telescope owners with limited space or
surfaces.
Click here for more information on integrated-control focusers.
TCF-Lynx Temperature Compensating Focuser
TCF Focuser 3-inch Models
TCF-S3 Large 3-inch Temperature Compensating Focuser

The TCF-S3 3-inch Focuser is the big brother of the TCF-S. This larger focuser is not only bigger, but stronger in order to accommodate the ever-increasing size of astronomical instrument packages. However, the upscaling process has not impacted the focuser's performance. the TCF-S3 maintains the high degree of optical and thermal precision necessary to create the exact focus needed for both film and CCD astrophotography.
Click here for more information.