Shooting an Interview with Auto Focus at DVinfo.net

Steve Lewis · June 28th, 2008, 06:10 PM

I am shooting a bunch of interviews in the next few weeks. In most of the interviews, I will have the subject to the right or left of the frame, leaving the center of the frame empty (or filled with the background) and I was wondering if the auto focus will fixate on the background b/c it is in the center or if the foreground speaker will be in focus. (I know I should ideally use manual focus, but I'd still like to know how the AF will behave) Thanks!

Richard Hunter · June 28th, 2008, 06:23 PM

Hi Steve. The auto focus will try to focus on whatever is at the centre of the image. Best to use manual for this situation, then you don't need to worry about the subject moving off to the side. And you can use a smaller aperture to give more depth of field. That will help keep it sharp if the subject leans forward or back.

Richard

Tripp Woelfel · June 28th, 2008, 07:30 PM

Steve... Often times interviews are a one shot deal and I would never trust an electronic brain over a human brain (or in my case, nearly human) to control critical functions, especially focus.

I never intentionally shoot a subject center frame. I'm a one-man crew so my interviews, when done on sticks and I'll step to my left out from behind the camera to talk to the subject, which draws their attention to me. So I frame them on to the right. Auto focus would go nuts trying to focus on the Eifel Tower or the moon or something much farther away than my subject. Bad idea all around.

I was also thinking about auto exposure, which I also think is bad in situations like this especially outdoors.

My mantra is to stay manual in all things unless there's a compelling reason to turn on the automation. There are times, but they are the exception, not the norm. At least with what I do.

Micky Hulse · June 28th, 2008, 09:30 PM

Great info Tripp and Richard!

I recently shot an indoor interview using a tripod mounted A1.

Setup: Inside large office building with windows/cubicals/open space in background. Two studio lights aimed at head/shoulders region -- zoomed-in center frame on the face -- white balance for the studio lights.

I had set the focus to auto, thinking there should not be any problems (basic head/shoulders center frame shot), and left it un-manned during the interview (I was using another A1 shooting secondary hand held footage)...

Long story short, when I finally got the footage captured, there was a minute+ long spot where the focus jumped to the objects in the far background!

Never again will I use the A1 auto focus in a situation like that.

Cheers,
Micky

Steve Lewis · June 28th, 2008, 11:00 PM

Quote:

Originally Posted by Micky Hulse

Long story short, when I finally got the footage captured, there was a minute+ long spot where the focus jumped to the objects in the far background!

Never again will I use the A1 auto focus in a situation like that.

I can sympathize! I often have my shots lapse from being foreground focused to background focused! Manual focus it is! One thing though: the tried and true trick of zooming into the eye, then manually focusing and then zooming out again doesn't seem to work on the A1... is this true for you guys as well?
-Steve

Oren Arieli · June 29th, 2008, 12:50 AM

Haven't had any issues with the tried and true 'zoom in, set focus, zoom out'. You should also be using the peaking and or magnify feature to double check your focus. I really dislike the LCD that Canon supplies, Sony's is much better in terms of sharpness and how they handle the focus confirmation.

Annie Haycock · June 29th, 2008, 02:49 AM

Steve - it could be that you are focussing on the eye when the person is relaxed, but then they lean forward when they are talking, and so go out of the plane of focus?

Steve Yager · June 29th, 2008, 11:33 AM

Quote:

Originally Posted by Annie Haycock

Steve - it could be that you are focussing on the eye when the person is relaxed, but then they lean forward when they are talking, and so go out of the plane of focus?

The XH-A1 can't acquire such a shallow depth of field that someone leaning forward would go out of focus, unless you zoom all the way in. I'd be more worried about composition than focus if I weren't manning my camera during an interview. Don't be afraid to tell the subject to try not to move around too much.

Annie Haycock · June 29th, 2008, 11:46 AM

It was just a thought - and it probably depends on where in the zoom range you zoom out to. Not being in the habit of filming people, I can only guess.

Micky Hulse · June 29th, 2008, 12:22 PM

Quote:

Originally Posted by Oren Arieli

..<snip>... Sony's is much better in terms of sharpness and how they handle the focus confirmation.

For sure... Peaking on my Sony FX7 is great!

I wish the A1 had a larger LCD.

June 28th, 2008, 06:10 PM	#1
Steve Lewis Major Player Join Date: Apr 2008 Location: Goleta, CA Posts: 233	Shooting an Interview with Auto Focus I am shooting a bunch of interviews in the next few weeks. In most of the interviews, I will have the subject to the right or left of the frame, leaving the center of the frame empty (or filled with the background) and I was wondering if the auto focus will fixate on the background b/c it is in the center or if the foreground speaker will be in focus. (I know I should ideally use manual focus, but I'd still like to know how the AF will behave) Thanks! __________________ www.spreefilms.com - Give me a museum and I'll fill it!

June 29th, 2008, 02:49 AM	#7
Annie Haycock Major Player Join Date: Dec 2007 Location: Pembrokeshire, Wales Posts: 734	Steve - it could be that you are focussing on the eye when the person is relaxed, but then they lean forward when they are talking, and so go out of the plane of focus? __________________ Canon XH A1; Canon XF100; Nikon D800

June 29th, 2008, 11:46 AM	#9
Annie Haycock Major Player Join Date: Dec 2007 Location: Pembrokeshire, Wales Posts: 734	It was just a thought - and it probably depends on where in the zoom range you zoom out to. Not being in the habit of filming people, I can only guess. __________________ Canon XH A1; Canon XF100; Nikon D800

June 28th, 2008, 06:23 PM	#2
Richard Hunter Trustee Join Date: Dec 2004 Location: Lipa City Batangas, Philippines Posts: 1,110	Hi Steve. The auto focus will try to focus on whatever is at the centre of the image. Best to use manual for this situation, then you don't need to worry about the subject moving off to the side. And you can use a smaller aperture to give more depth of field. That will help keep it sharp if the subject leans forward or back. Richard

June 28th, 2008, 07:30 PM	#3
Tripp Woelfel Trustee Join Date: Jan 2008 Location: North Conway, NH Posts: 1,745	Steve... Often times interviews are a one shot deal and I would never trust an electronic brain over a human brain (or in my case, nearly human) to control critical functions, especially focus. I never intentionally shoot a subject center frame. I'm a one-man crew so my interviews, when done on sticks and I'll step to my left out from behind the camera to talk to the subject, which draws their attention to me. So I frame them on to the right. Auto focus would go nuts trying to focus on the Eifel Tower or the moon or something much farther away than my subject. Bad idea all around. I was also thinking about auto exposure, which I also think is bad in situations like this especially outdoors. My mantra is to stay manual in all things unless there's a compelling reason to turn on the automation. There are times, but they are the exception, not the norm. At least with what I do.

June 28th, 2008, 09:30 PM	#4
Micky Hulse Major Player Join Date: Jul 2007 Location: Eugene, Oregon, USA Posts: 213	Great info Tripp and Richard! I recently shot an indoor interview using a tripod mounted A1. Setup: Inside large office building with windows/cubicals/open space in background. Two studio lights aimed at head/shoulders region -- zoomed-in center frame on the face -- white balance for the studio lights. I had set the focus to auto, thinking there should not be any problems (basic head/shoulders center frame shot), and left it un-manned during the interview (I was using another A1 shooting secondary hand held footage)... Long story short, when I finally got the footage captured, there was a minute+ long spot where the focus jumped to the objects in the far background! Never again will I use the A1 auto focus in a situation like that. Cheers, Micky

June 29th, 2008, 12:50 AM	#6
Oren Arieli Major Player Join Date: May 2007 Location: San Jose, California Posts: 918	Haven't had any issues with the tried and true 'zoom in, set focus, zoom out'. You should also be using the peaking and or magnify feature to double check your focus. I really dislike the LCD that Canon supplies, Sony's is much better in terms of sharpness and how they handle the focus confirmation.