Building a Custom Focus Control System

This video, requested by some of my viewers, shows how I built a custom remote focus control setup for three different astrophotography rigs. I have used the Sky-Watcher Autofocus Kit and the Hitec Astro DCFocus Controller in all of these rigs, but alternatives can of course be used. I use low cost GT2 pulleys and belts, Arca Swiss clamps and plates and some home made metal blocks/plates to fashion these setups, and they have served me well over the last few years. You may want to follow my steps exactly, or perhaps you need to do something similar for a different rig, and my video will simply give you some ideas on how to go about it. Either way, I hope you find it useful. Below are links to some of the key parts I used:
Sky-Watcher Auto Focuser
Available from First Light Optics, Rother Valley Optics, Widescreen Centre and other Sky-Watcher distributors. Cost ~£57
HitecAstro DCFocus V2 (DC focus motor Controller)
First Light Optics, Tring Astro, Cost £79
(I actually used the original version, but I suggest using the V2 version now available)
Canon Lens Setup
===============
GT2 6mm Pulley, 40 teeth
www.amazon.co.uk/gp/product/B...
GT2 Closed Timing Belt, 350mm
www.amazon.co.uk/gp/product/B...
Sky-Watcher Quattro 8CF Setup
=========================
Thumb Screw, M6 x 20
www.amazon.co.uk/gp/product/B...
GT2 6mm Pulley, 60 teeth
www.amazon.co.uk/gp/product/B...
GT2 Closed Timing Belt, 228mm
www.amazon.co.uk/gp/product/B...
Also, please do check out my website at www.martinsastrophotography.com for information on my equipment, tutorials, free sky calendars, handy tools, my image gallery and more.
Clear Skies!
----------------- Chapters in this Video -------------------------
00:00 - Focus Control System Introduction
07:51 - Camera Lens Focus Control Systems
26:57 - Newtonian Focus Control System
34:48 - Wrap-Up

[@w8bya]

Very nicely done ! I was hoping you would show a homebrew DC motor or stepper motor setup controlled and autofocused via PC remote control and one of the software applications you mentioned. I think there are many who would like to see the final piece of the puzzle. TU

[@jayantbheda]

Thank you for a thorough and succinct presentation for someone to follow.

[@martinsastrophotography]

Thank you Jayant. I really appreciate your positive feedback! Clear Skies.

[@lsa168]

Nice job!

[@martinsastrophotography]

Thanks Larry. Clear Skies.

[@juanjose1173]

Very nice video Martin, well structured and very well explained. Thanks !!

[@martinsastrophotography]

Thanks for the positive feedback Juanjo! Much appreciated. Clear Skies.

[@nathanmay3658]

Great video. As others have said, well structured and clearly presented. Been shooting with my 100-400 and this seems like a worthwhile project. Thanks much!

[@martinsastrophotography]

Thanks Nathan. Really appreciate your comments. Clear Skies.

[@AstroSoundscape]

What a great design thanks for sharing.

[@martinsastrophotography]

Thanks for that Oli. Really appreciate the positive feedback. Clear Skies.

[@briansnell9179]

Excellent video Martin, well explained with useful info on parts etc. I have been considering adding an auto focus to my set up for a while now and this video should help. Plus as you only live 1.5 miles away from me, if its OK with you, I might want to pop over for advise if I have a problem with adding a focuser.

[@martinsastrophotography]

Thanks Brian. Sure…you are welcome to pop round!

[@NunoAg]

Hello Martin! Thanks for the video!!! One question. Is this system fits on a non dual focuser like skywatcher starquest?

[@martinsastrophotography]

Possible, but not an easy job!

[@christopherleveck6835]

I know this is an old post.....but.... is there a way to use this with an ASI AIR?

[@martinsastrophotography]

In all honesty I would go for a ZWO EAF 5V now. Better fidelity control!

[@christopherleveck6835]

@@martinsastrophotography I've already got nearly $1,000 worth of moonlite focusers for my Explorer Scientific ED102 and Celestron 8" SCT....
Plus I made myself a couple of cheap and easy My Focuser Pro2's for big dob and DSLR's....
By the way, have you seen SVBONY has a Canon EF adapter?
I use it with a 100mm f/2.8 MACRO lens....
You'll think I'm nuts, but if you want a flat field of view with edge to edge pinpoint stars....
In the beginning I was too noob not to try it.
At 100mm on my old T3i DSLR I could perfectly frame the lower half of Orion or the entire California Nebula......
And there's nothing cuter than an ASI178 on a Canon f/1.8 Nifty 50 lens...
Have you ever tried to Frankenstein or DIY an adapter to plug into the motors INSIDE a standard autofocus EF lens?
Im not sure if the motors are inside the lens even, but that would be an AWESOME hack.
What I like about your setup is the use of DC motors. That really opens up some interesting possibilities.
Last thing, for now anyway, what happens when the motor runs out the end of the focus adjustment on the lens?
My macro lens will turn indefinitely. Not sure if thats a feature or if it's actually broken. I have a couple of Nifty 50's and the focus adjustment on them hard stops... Pretty sure if the focusing motor didn't stop at the end of the focus ring travel on the lens something would be unhappy. Can you adjust the belt tension to slip?