Autofocuser FAQ

While testing our units, we carefully write down every issue that arises and solution to it - from basic connectivity, firmware upgrade to more complex problems like focuser slip and play. In result, this section composed from development and testing experiance, gathered from countless nights through years of astrophotography in field. Should you have additional questions not listed here, please let us know!

When I connect the autofocuser to computer, it is not recognized. What can I do?

You probably need to install the CH340 driver for Arduino compatible boards to provide USB connectivity. You can download it here or from authors website.

How can I upgrade focuser firmware?

Please refer to the firmware upgrade instructions.

Focuser is recognized by Windows and virtual COM port is created. What now?

Next step is installation of ASCOM driver, so you can use the focuser with any of the automation programes, like SGPro. You can download the ASCOM driver here. You also need to install ASCOM platform.

I successfully installed new version of ASCOM driver, but old version is still being used. How can I fix it?

This happens sometimes, expecially if driver is in use and you run ASCOM driver setup in meantime. ASCOM closes program using it, but in some cases it still does not work. To install new version of driver, delete the following dll file: C:\Program Files (x86)\Common Files\ASCOM\Focuser\ASCOM.DeepSkyDad.Focuser.dll and run installer again.

I successfully installed new version of ASCOM driver, but now focuser will not connect. How can I fix it?

First check if you chose the correct COM port. If that does not work - ASCOM driver is developed for specific version of autofocuser firmware (specified in the readme file). We recommend you to always use latest firmware and latest ASCOM driver in downloads section.

Can you explain the ASCOM driver settings?

ASCOM driver settings can greatly improve autofocuser in some cases:
  • COM port - virtual COM port, assigned to your focuser.
  • Step size - supports step sizes from 1 to 1/16. Generally, we recommend 1/4 step size, but in some cases (no 1/10 knob for example) other step sizes are more appropriate.
  • Max. position - maximum focuser position. 10000 should suffice for most use cases.
  • Settle buffer - if your focuser has any play, this can affect the autofocuser performance. SGPro for example goes aways from current position and than starts traversing back. When it changes focus direction (traverse back), focuser play can cause FOV to jiggle just a bit, which causes enlongated stars on the next exposure. Settle buffer option returns IsMoving as TRUE for specified time after focuser reaches target position, letting it to settle a bit. This only works well from SGPro version 3.0.0 beta and later.
  • Trace on - ASCOM driver trace log. If you experiance autofocuser issues, turn this setting on and send us the log files. They are located in "C:\Users\username\ASCOM" (Windows).
  • Reset settings on next connect - if you experiance weird focuser behavior or for example hit 0 or max focuser position, you can reset the focuser with this setting (this setting auto clears after next connect).
  • Always on - when this setting is on, stepper motor coils are powered all the time, holding the stepper position. This can serve as focuser locking mechanism for focusers with slipping issues.

How can I use the focuser in combination with the rest of my equipment (camera, guiding, mount...)?

Mounting of focuser is up to the customer, as stated in IMPORTANT section of autofocuser page. We recommend you mounting via timing belt, because it is less invasive to the focuser than shaft to shaft coupling. That is why every focuser comes with MXL pulley and free option of timing belt with various lengths. We also separately sell 3D printed mounting adapters for a few focusers. You can check more in autofocuser mounting adapter section.

Can I control the focuser manually?

There is no manual controller for the focuser since it is meant for astrophotography. However, you can control it from any software that supports ASCOM standard, for example SGPro.

When focuser is turning, it causes vibration. What can I do about it?

Some amount of vibration is normal with stepper motors, included in our focusers. If you are using full step or half step mode, try to change it to 1/4 or 1/8 in ASCOM driver properties and increasing number of steps per change in SGP.

SGPro autofocus graph spike on right is causing smart focus to move away from in-focus position instead of towards. How can I fix this?

This can happen if you have any play in the focuser drawtube. Please check Settle buffer in ASCOM settings section.