QHY QFocuser Electronic Focuser - High Precision Version - 110137

QHY Q-Focuser - High Precision Version

The QHY High Precision (HP) version on the Q-Focuser installs on the precision adjustment axis side of the your focuser. While the Standard version of the QHY Q-Focuser is designed to be installed on the course adjustment axis side of the telescope.  

The main difference between the HP & Standard version, besides which side of the focuser it is installed, is the type of motor used.  The High Precision version uses a motor without reduction gears, while the Standard uses a motor with reduction gears. Because of this difference, the two versions perform a bit differently in these areas:

Size, weight & cost:  Standard is a tad smaller & lighter, and it costs a bit less

Manual focus:  HP version supports it, while the Standard does not

Backlash:  HP version wins here with less backlash to begin with (reduction gears cause some backlash), although any backlash can be calibrated with the use of NINA software.

Max load:  The Standard version is listed at 10kg while the HP is about 7.5kg.  

As you can see, there are pluses and minuses to both versions of the Q-Focuser.  If you have a heavier load, then the Standard may win out, but the ability to manually focus and start with less backlash before calibration will probably make the HP version a winner for many.

PS:  The Q-Focuser does not fit Schmidt-Cassegrain or RASA telescopes.  If you'd like to use it on one of these fine telescopes, wait a bit, as we hear an adapter is being developed.  

PPS: Also, please note that the Precision Version comes with 2.5/3/4/5mm couplers.  Check the diameter of your bearing before purchase to make sure there is a coupler size that will fit your equipment.

The Q-Focuser High Precision is very small & lightweight!  Its curved surface design provides some extra clearance while weighing just 265g.  The Q electronic focuser dimensions are 43 mm x 39mm x 50mm, excluding the knob.  Its max load is about 7.5kg.

Most electric focusers use a motor and reducing gears and once installed on the telescope manual focusing is not possible. However, the High Precision QFocuser is equipped with a non-reducing motor, allowing it to be manually adjusted even after installation on the telescope, without the need for a power connection or a clutch switch.

Another advantage of QFocuser High Precision Version is that it allows the entire system to achieve almost zero backlash. Backlash calculations involve the entire focusing system, including the focus motor mount, not just the electronic focuser itself. Backlash will exist if there are mechanical gears in the focusing system. Since the High precision QFocuser uses a non-reducing motor (i.e., no mechanical reduction gears) the added backlash from the motor is almost zero. Then, if a good focusing mount is used, the entire focusing system will operate with almost zero backlash. According to our test in NINA, with the backlash set to 0 in the Autofocus settings, the autofocus process runs smoothly.

QFocuser features several holes on its bottom and side, providing a variety of fixing methods. Unlike mounting plates with fixed holes, QFocuser adopts a flexible structure where the fixed holes position and mounting plate height can be freely adjusted to achieve the best compatibility with your telescope.

Read more about the Q-Focuser...