Astromechanics EOS Focuser and autofocus

i m trying for the first time Voyager software .
I m using an ASI cam and canon lens with the Astromechanics EOS Adapter which permit remote focusing .
This focuser is not an absolute one it seems, it always start at 5000 steps

Is the autofocus routine in Voyager are ok for this sort of focuser ? Im using right now EKOS and i can do autofocus with it. I just roughfly make the first focus by hand and after autofocus work .

Is there anybody using this Astromechanics focuser ?


Hi Florent,

if the driver ASCOM of your focuser is declared like not absolute mode focuser it isn’t compatible with Voyager, otherwise answer is yes.

Important Note! RoboFire Autofocus doesn’t allow use of focuser with relative driver movements mode … only absolute ASCOM driver

All the best

Hi Florent,

I use this adapter too and I go very well with Voyager. I use it with ASI2600mm / mc on Canon EF 200mm / 2.0, Sigma 105mm / 1.4 and Sigma 40mm / 1.4. I make the sequences using a script. At the beginning of the script I test the focus of the configured optics and if it falls within these 3 I make a goto of the ascom focuser at 20,000, which is well beyond infinity. In this way I set the value of 20,000 as an infinite full scale. Right after that I do a 5 second delay and then a goto at 19,270 which is about focus. I have seen that these values are compatible with all my lenses. At this point I proceed with the focus, both on the star or in the local field and it works very well. Below is an excerpt from my script.

First determination

and then focusing


Obviously you must have drawn the vcurves first.
I hope I was helpful.


Hi Marzio
Thanks for your response and your help

it is a nice idea to foce the focuser to the infinite , that what i m doing manually when installing my setup so i ve just to go inward to find the rough focus point .