Quickfocus in video mode?

F

Frank Bongers

Member
I am posting this message to get my question cleared up ... since I'm unable to verify it myself.

I was always under the impression that if you are using an autofocus lens while shooting video, the lens would be "downgraded" to manual focus only.

Recently I'm reading some contradictory messages that you *can* focus while recording video. Is this correct? While I'm positive that it's not "continuous" focus, I see people that claim you can just push the shutter button slightly and it will focus during video recording. Well, I know that works fine for photos, but when I try it for video ... it just doesn't work.

Am I missing some vital information to make this happen? Or am I being fed wrong information? :undecided
 
I don't think you can 'auto focus' during video recording. You can however 'manually' focus with the lens while recording video.
 
Well, I don't *want* to autofocus, but a bunch of websites mentioned you could do it - just like in photo mode - so I was wondering if I missed some setting or so.

Note: the reason I thought I missed something is that when using the EOS utility - and put it in video mode, you *can* focus using the focus button in the software. So I was wondering why it wouldn't work in video mode.

Reason why it would be useful: before you set up a shot and while recording - you could quickly focus without adjusting your lens manually.
 
Well to clear this up once and for all as we all seem to end up reading lots of things by people on the web who probably don't even own the camera.... (I'm not saying anyone in this thread is included in that).

ABSOLUTLEY YES you can autofocus during video recording - at least you can with my 7D with a AF Canon 17-55 USM IS EF-S lens with AF left switched on - so why not with any other AF lens. It's easy. Just press the AF-On button on the back while you're recording.

As indicated...NO you probably don't want to (most of the time - unless it's a quick reframe/refocus at a point where you'll chop out a few seconds in editing - where this method can be pretty useful if you want to keep rolling to capture audio for example).

You can also manually focus at any time with my set-up too, regardless if your are recording or not (and the lens AF is switched on or not)!

Hopefully this is now clear for everyone.
 
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And I'll second Andy's assertion, although he's "cheating" since he found the AF button where others aren't RTFM and instead were pressing the focus button on the top of the camera (only functional in traditional SLR mode).

Way to go Andy!

Regards,

Michael
 
*That* was what I wanted to read - Thanks a lot!

And yes, I'm one of those morons that pressed the shutter button to focus - and I didn't read the manual of course :)

Andy, thanks ... and I hope this thread will answer other's questions as well.
 
To put it simple...

Can you auto-focus in Video Mode? Yes.

Is it good enough to use? No. While it's useful to set an initial focus point, it's not good enough to focus during a take. It's far too slow, it searches all over the place and it temporarily increases the ISO to find focus, which changes your exposure for a second or two.
 
True, it's nowhere comparable to a "real" camcorder. But despite the AF limitations, it's often WAY faster than a human. Besides, isn't that why we take B-Roll cutaways for situations like this?

Happy Trails, Michael
 
I am currently shooting with two GH1s and what I hate about the GH1 auto-focus is that it's either continiously, or off. You cannot "push focus" with it. From this topic I understand that with the 7D, push focus is possible. Yes, it may mess up your footage for a few seconds ("slow, it searches all over the place and it temporarily increases the ISO") but you edit that out. Manually focussing without a follow focus takes longer than 2 seconds and causes camera shake one way or another.
 
Frank Bongers said:
Reason why it would be useful: before you set up a shot and while recording - you could quickly focus without adjusting your lens manually.
Click to expand...

Exactly. This is how I have been doing it for years with video camcorders and it's great if we can continue doing it like this with DSLR filming.
 
Something else to note: there are three autofocus settings for the Canon EOS 7D.

One-Shot AF
"Suited for still (ed. - as in not moving, not still photography) subjects. When you press the shutter button halfway, the camera will focus only once." - Canon EOS 7D Manual, p. 85

AI Servo AF
"This AF mode is for moving subjects when the focusing distance keeps changing. While you hold down the shutter button halfway, the subject will be focused continuously." - Canon EOS 7D Manual, p. 86

AI Focus AF
"AI Focus AF switches the AF mode from One-Shot AF to AI Servo AF automatically if the still subject starts moving." - Canon EOS 7D Manual, p. 86

I really haven't looked at the AF very much on my camera - I generally punch in and use critical focus since I have been that time limited. However, I would imagine that one of these settings is superior for certain uses. I would think that if you had AI Servo set and were trying to focus on a still subject it would take a rather long time since it is trying to capture the movement.

Yet another reason to shoot some camera tests today!
 
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