SharpSky Pro stepper based focus control / motor

[dmahon]

I haven't seen much written about this SharpSky Pro unit, but when I found myself wanting a stepper motor based focus controller, so I could truly autofocus (unlike the Skywatcher Autofocus unit which has a DC motor) it looked like something worth giving a go.
 
It has a couple of nice touches:
 
1) USB based rather than serial (I only have one serial port which is in use, so I'd have needed a USB-serial convertor anyway)
2) Built in 4 channel Dew controller
3) UK made, and in the southwest at that
 
It started off as a home made item, which was then supported in kit form and has progressed to a very professionally made unit together with ASCOM driver. I ordered mine on New Year's Eve and it arrived today (next day, excluding the bank holiday). He had kindly fashioned the mounting bracket for my scope, so all I had to do was attach it (you are normally given a blank that you can drill for your specific focuser). I haven't had the opportunity to try it out in anger, so to speak, given the weather - but it works as expected otherwise. Here are a few pictures:
 
In the box:
 

 
Out of the box:
 

 
Attaching to Skywatcher Equinox 80 - some stand off screws were provided and the 10:1 fine focus knob was removed:



The whole unit connected up:


 
Front of unit (manual controller, cable to stepper motor, USB cable):



Back of unit (power [not captive], dew controller [1 inserted]):

It can all be controlled manually, but it comes complete with an ASCOM driver. It has an external temperature probe and a temperature probe within the motor unit.

More details on their webpage: http://www.sharpsky.net/index.html

[Steve Jackson]

I have one of these too and have been over the moon with it so far, Dave is a friendly guy who is always willing to help if you have any issues.

At the moment I am using it as a Dew Heater but will be on my WO GT-81 as soon as I work out the best way to attach it.

[dmahon]

I tried it in a moment of clear sky, and am happy to say I got the autofocus routine in SGP working straight away (though I have probably not found the best settings yet). Putting a Bahtinov mask on the scope afterwards, it looked pretty much spot on.

I'm surprised on of the major retailers hasn't jumped on him to act as a main supplier - as he's based in the southwest, FLO would seem like the obvious choice.

[Steve Jackson]

I expect it's down to the time and effort involved, I know he builds all of the units himself.
The number of people using a focus unit such as this must be rather small though.
 
Had a few problems with software crashing or working strange, I'm 95% sure this is down to using OSX and Boot Camp/Parallels to run Windows rather than a PC.

It definitely does a better job at focusing than I do! lol

[continuum]

Only just seen this thread, but I have one of the original kit based focusers. This has worked faultlessly and as it  has the same base as the Pro version I would recommend it thoroughly.

Ron

[ChrisLX200]

Just today I received a SharpSky kit from Dave, a controler plus two motors (two scopes will motorised but not run together at the same time, so I only need one controler). The motors are a little bigger than I expected so I've had to re-think the method I was going to use to mount them. Rather than using direct drive - with the motor sticking out from the end of the focuser - I'll be using some MXL toothed pulleys and belts. I want the motor sitting either on top or below the focuser for a more compact arrangement, and using a 2:1 reduction will give the motor some extra leverage. Glad to hear others have had success with this kit, at the moment I have mine just wedged in place temporarily while I play with the software (running SGPro). I don't know if I will ever make use of the temperature compensation adjustment, it would seem to be difficult to calibrate? I think a quick auto-focus check between subs might be better, but that will be for later.

Just a few photos, a temporary setup like I said.

ChrisH

[Tonk]

Looking forward to mine arriving in the next week or so - just ordered one for a remote controlled rig to be operated in Spain from the UK.