Remote follow focus for £150/$300

Well the problem with a standard servo is the gearing has mechanical limits that stop it rotating over 180 degrees (or 200 in the case of the hitech metal geard quater scale servos)

Thers a peg that sticks up out of the top of the gear that stops against a moulding in the top of the case. To get 360 degree rotation you have to grind this off, but then the potentiometer can be damaged as the pot can only move 180 degrees.

There is one servo that will do 3.5turns positional as standard but its quite slow and its not very accurate.

Theres no easy way to make a normal servo do 360 degrees positional operation.
 
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The potentiometer is no longer there, so how can it be damaged? You are correct, no easy way......but there is a way. How do you think the pro systems get round it? This problem is like doing a Crossword, you have to think laterally
as far as the Pot is concerned, IT can actually move 270 degrees.
If you are in the UK you will see my system for sale hopefully. You can buy one, and then say It does not work.
 
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Il buy one, Im having quite a few problems with my system unfortunately.

The pro systems dont use servos though do they, they use geared stepper motors which can do 360 degrees proportionally without modification
 
Follow Focus

Follow Focus

hoarp001 said:
Well if a £1000 focus motor has a hitec servo inside it then they are charging too much.
Click to expand...


Hoarp... try looking at small stepper motors. They are really small these days.
There are chips that will drive them very easily. The thing about steppers is that you can move it a step at a time. Therefore you Know exactly where it is at a given time.
Go for a wired system firstly, and then go wireless. You need a guy who can design the electronic side of things for you.
It's obvious you know what is needed, but you need a 'techy' to design the electronics.
Good Luck!!
 
http://uk.youtube.com/watch?v=HpQWm759NW8

Quick update.

I managed to get the motor to move the whole focus on my 28mm canon FD. Still abit short on some of my other lenses but Il get there in the end.

My laptop didnt record sound for some reason, but the motor whines a little bit, but its quite quiet.

Let me know what you think
 
What's the thickness of that gear (the white one)? It would be great if you can have a thicker gear like the Redrock FF so that it doesn't slip.
 
Its about 5mm wide. It has a spring to hold it to th e gear, even with my stiffest lens (big old canon zoom) it dosnt skip teeth
 
He's pretty much building the one thing we all know we've wanted to build ever since we got the 35mm bug and realized we needed a follow focus.

Good one on you dude: you still have my money and my vote of confidence that you;re gonna pull this off.
 
Another quick update:

I took the RFF on a film shoot today with a redrock and nikon primes. The RFF was brililant, its so accurate, and its practically silent. Even the on board mic that was 5 inches away from the motor didnt really hear it moving.

Also theres a major upgrade coming to the system... Im replacing the wire for something a little bit more practical... any guesses?!

http://www.youtube.com/watch?v=prZ6mlyTBmM
 
sweet! you're actually going to be able to make it wireless???

if that bumps the price up significantly, maybe you can still offer a wired solution. even being tethered by a cable would be better than a whip...
 
Yeah Im still doing the wired option. The plan is to make the wired one upgradable. If you want it wireless, send it back and I can put the wireless module inside it and send it back with the receiver. Uses the same motor.
 
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