View Full Version : Video Autofocus full frame?


Clive McLaughlin
February 24th, 2014, 05:13 AM
A quick question guys - I've been planning to upgrade my b cam (for steadycam) for a while. I've been really tempted to go for a Canon 70d for its autofocus in video.

But the think thats been annoying me is the quality difference between my 550D and my full frame 6D. This is unlikely to change much upgrading from 550D to 70D.

Is there a full frame DSLR out there or on the horizon with this video autofocus technology?

Clive McLaughlin
February 24th, 2014, 07:01 AM
I’ve just discovered the Sony A7 and A7r have autofocus in video mode and are full frame.

Rainer Listing
February 24th, 2014, 03:25 PM
Not to mention the auto EVF. But they don't have 50i/25p frame rate.

Brian David Melnyk
February 25th, 2014, 04:16 AM
Since buying a 70d, my 5dmii has become the b camera... Even with magic lantern.
It is just so much better for run and gun. And I am very happy with the images it produces, even at fairly high iso.

Clive McLaughlin
February 25th, 2014, 04:35 AM
Brian, do you use the autofocus?

I was hoping it would be good but I'm rather concerned now. Plan was to fly it on a steadycam.

Found this online - uploaded by Taky Cheung who posts on here sometimes.

Was instead tempted to get another 6D so my quality matches better and stick with manual focusing.

Not liking the look of this at all.

Canon 70D Face Tracking - YouTube

Danny O'Neill
February 25th, 2014, 05:23 AM
I had a read of their papers on the AF and it only focuses on whats in the centre of frame and cant be moved. So in the shot you show it would have the officiant in focus but not the couple.

Also no good if you like to have your subject just off centre.

Same goes for the C100/C300 with the Dual pixel upgrade.

Also the smoothness of the shift depends on the lens used. Standard EF lenses can be a little jumpy but their new STM lenses are smoother.

Steve Bleasdale
February 25th, 2014, 05:37 AM
Since buying a 70d, my 5dmii has become the b camera... Even with magic lantern.
It is just so much better for run and gun. And I am very happy with the images it produces, even at fairly high iso.
Brian what is the isle shot like dad and bride are they both in focus or is the camera switching one to the other, are you working at 2.8, f4, 5.6 on that shot. cheers steve

David Dixon
February 25th, 2014, 09:44 AM
I thought that on the 70D you could pick the focus area via the touchscreen, but on the C100 (and now the C300) it was center only, although with a focus lock and recompose option...

Dave Partington
February 25th, 2014, 10:03 AM
Not liking the look of this at all.

Once in the ceremony the AF is the first thing I turn off because I don't want it wandering around.

This is a perfect example of when AF is not the right tool for the job. How can we expect the camera to know which person it's supposed to be focused on at any given point in time? That's what the camera operator is for :)

Robert Benda
February 25th, 2014, 01:26 PM
Once in the ceremony the AF is the first thing I turn off because I don't want it wandering around.

This is a perfect example of when AF is not the right tool for the job. How can we expect the camera to know which person it's supposed to be focused on at any given point in time? That's what the camera operator is for :)

Exactly. I watch that three shot and wonder why he has AF still on, OR, why doesn't he keep his finger where he wants it, or use a different setting for AF so it doesn't hunt like that.

I love the AF for the entire rest of the day, just not the stationary moments like the pastor's message and vows.

Clive McLaughlin
February 26th, 2014, 03:19 AM
I really feel like I need to trial one before I would be happy. I mean, if i was panning a long a group of people say outside the church where you see the backs of people and other faces of people talking to them, would the AF not jump from face to back of head to face etc?

I'm starting to think I should just get another handicam for church auto stuff and stick with manual focus for my steadicam and get another 6D to keep the quality up at a high standard.

Brian David Melnyk
February 26th, 2014, 08:30 AM
I don't do weddings, but I do film run and gun.
The autofocus on the 70d has three different modes, one with facial and object tracking that can be menu adjusted in increments between locked-on and responsive, a zone setting that you can pick between centre weighted focus, left or right frame focus, and strictly centre. The third mode allows you to pick any point in the frame to focus on with a small box. You can pick points by touching the screen softly or by the multi controller around the set button. You can assign a button to disable auto focus after you pick a focus point (you have to keep holding it down) or suspend it completely by the touchscreen or by pressing the flash pop up button.
It can be quirky, but if you choose the auto focus method wisely, and disable it when you want to lock it, it is a really intuitive process that can focus far better and more fluidly than I can, even with magic lantern and a follow focus. Keeping the camera steady while interacting with the auto focus (more like manual-auto-focus!) is easier for me also.
For steadycam, though, I use an xa10. I have an old Merlin with a plate not designed for dslr, so balancing it was not optimum for me. So not sure about the autofocus of 70d for that purpose, but I do know the autofocus works better when you are micro managing it a bit, which is not a great option for steadycam.
But it might become you A camera while you fly the 6d...

Brian David Melnyk
February 26th, 2014, 08:46 AM
I know Taky is a knowledgable pro, but that video represents user error, in that the wrong autofocus method was chosen (you cannot expect a camera to read your mind which face out of three you want to focus on), and it could easily have been locked off after finding focus. Leaving the camera on a tripod to focus as it pleases is maybe not a great idea when the scene is more complex- it will get confused. One face, maybe...
A centre weighted focus would more likely hold its focus and not shift around, or locking on to the mic as a middle ground focus point would be better, but I would still micro manage a dslr, with its smaller depth of field, or lock it off in that situation...