Dunno if there already exsist but wouldn't it be smart with a little reciver/device thingy that you could put into your pocket, it sends a singel back to the camera and the camera canculates the distance and sets the focus to that distance. So you could move around how wide and fast as you'd want and the dof always stays at place =p
Focus Device
- Thread starter NuclearHamster
- Start date
So the actor has a transmitter on them and the camera keeps focused on them? I love the idea in theory, but in practice I don't think it would work out. Wireless follow focus systems are enormously expensive anyway, so people that could afford your system would probably be able to afford a (more reliable) manual wireless follow focus and 1st AC.
Also, what happens when you're shooting with razor-thin depth of field? The actor might have the transmitter in their front pocket, putting their nose in focus and their eyes out. If they turn around and walk away from the camera, it'll be focusing beyond them rather than on their back.
If there was a product that did this that was cheap and worked well, I'd buy it (who wouldn't?) but I think the applications for it are just too limited (and I'd rather have a good 1st AC).
Also, what happens when you're shooting with razor-thin depth of field? The actor might have the transmitter in their front pocket, putting their nose in focus and their eyes out. If they turn around and walk away from the camera, it'll be focusing beyond them rather than on their back.
If there was a product that did this that was cheap and worked well, I'd buy it (who wouldn't?) but I think the applications for it are just too limited (and I'd rather have a good 1st AC).
novel concept.. auto focus 
There are already hideously expensive systems that involve very very very fast processing, laser range finding, and remote focus control which do basically exactly what you describe. They're used for things like automotive racing, extremely fast action, stuff like that. And there's still a focus puller in the mix. In many cases the 1AC will be concentrating on the pull, and the 2AC will be acting as the spotter, calling out distances either visually or from the laser-finder - especially in shots where something is moving extremely fast into the lens.
thats cool David, Id never thought how high speed races might deal with focus..
I'll admit to describing a bit of the old way there, but still lots of it done. There's these as well, which you'll probably get a kick out of:
http://www.prestoncinema.com/products_light_LR.html
$600/day and $100K in equipment insurance and you too can have one on set!
A bit on the cost prohibitive side.Of course with a name like "Preston Light Ranger" it sounds like something from a table top strategy game based on the movie Equilibrium.