View Full Version : AF please........


Gregg Holland
March 1st, 2013, 11:00 AM
Hello everyone, first post from Sonoma County, a total newbie but all in!! When, why hasn't someone developed a smooth AF for video in the higher end camera's? Believe it or not the Rebel has a respectable system but the content is not broadcast quality.....yet. My new rig, standing by for a year of boot camp. "Nice! back to 1, this time faster up the stairs, skip a riser if you can....ready Gregg....ready......Gregg?

http://i209.photobucket.com/albums/bb236/greggh_fish/photo-92.jpg

Chris Medico
March 1st, 2013, 02:03 PM
It is because a good focus puller will be way better than an AF system any day.

Gregg Holland
March 1st, 2013, 02:34 PM
Perhaps now but I'm guessing in 2 years someone will have a killer AF that will be able to handle multiple subjects in the same frame. Again, a sorry newbie here but why can the Rebel pull a decent move but the other higher end SLR's can't, is it a simple pixel count challenge? I get the AC's place in this but a remote FF and the added crew and cost is a real bummer.

Khoi Pham
March 1st, 2013, 03:04 PM
That will probably not going to happen soon with full frame camera because of dof. and like Chris said, auto is not good enough and how does it know what you want to focus on and when to pull like rack focus or many other things that manual can do.

Ben Lynn
March 1st, 2013, 07:06 PM
I agree with Gregg that the focus needs to be improved in our dslrs but maybe not through AF. That's definitely an option and could be helpful if it had some face detection. At least then the camera could hold focus on a subjects face.

The problem I've found is the form factor of the cameras combined with the lens types. The cameras aren't set up in a way that's conducive for holding the camera and rolling focus (I work in tv so we use "roll focus"). The form factor is great for film style work but not so great for eng style work. I've been trying to adjust my shot style for this because I just moved over from a JVC HM700. What I think we really need is a zoom lens with a grip so that we could zoom AND focus at the same time but that's just a wish list :-) I think that if a person could grip the lens better and get a good view of the lcd screen then it could help with the focusing problems a lot of people run into. I really with the 5D had the swivel screen like the 60D but again, put that on the wish list with the other items. If any camera were perfect, we'd have nothing to talk about on these forums!

Matt Davis
March 4th, 2013, 07:16 AM
There are systems like the Hocus Focus: Hocus Products (http://www.hocusproducts.com/) - having someone actually eyeball a critical focus pull has won over autofocus for some time now.

The reason being that Continuous Auto Focus is notorious for drifting off and getting excited by the background.

Epic/Scarlet and the FS700 have 'tap to focus' touch screens, which do help, but are not 'auto focus' as such. Just another focus aid.

Another FS700 development borrowed (stolen?) from the consumer market is 'face focus' - look for areas of skin tone, look for contrast inside that area (usually eyes, mouth) and follow that. There's also the Phase Detection AF lenses using a split mirror - these have no 'hunting' and are blindingly quick - quick enough for the FS700 slomo.

But these tend to require 'fly by wire' controls for the lens, so there's no manual connection from focus ring to focus mechanism. This makes them a beast to drive in manual. It's not been popular in the world of Canon glass (though there have been attempts).

The Canon DSLR continuous AF is still liable to get a little jittery, and can freak out. Wouldn't want that to happen on the otherwise perfect take as the light fades (and the operator's full of lactic acid...).

So at the pro end, we end up going back to focus pullers on wireless controllers. Sigh.

Chris Hurd
March 4th, 2013, 10:04 AM
Duplicate threads merged.