Depth of Field at DVinfo.net

Pete Cofrancesco · June 26th, 2009, 01:48 PM

I have been told when filming theatrical performances to manually focus on the back of the stage and everything in front of that point on the stage should be in focus. Seems to me focusing in the middle would give me dof to work with. I also ran a dof calculator and it says you have more dof behind the subject than in front. @50ft f/2.2 54mm = 5.5' in front / 7' behind subject.

Bruce G. Cleveland · June 26th, 2009, 02:24 PM

Quote:

Originally Posted by Pete Cofrancesco

I have been told when filming theatrical performances to manually focus on the back of the stage and everything in front of that point on the stage should be in focus. Seems to me focusing in the middle would give me dof to work with. I also ran a dof calculator and it says you have more dof behind the subject than in front. @50ft f/2.2 54mm = 5.5' in front / 7' behind subject.

Pete wouldn't that depend on the iris setting? If you are shooting at 2.8 and zoomed in, for instance, you will have a very narrow dof, so the curtain would be in good focus, but everything else even a small distance away would be blurred.

Bruce

John Estcourt · June 26th, 2009, 02:39 PM

I think the rule is 1/3 in front 2/3 behind for DOF
I always set the focus before the start of a show, zooming in on the middle of the stage and setting that as my focus point.
That should cover you except perhaps max zoom in low light when you may need to re focus due to the wide open iris.

Pete Cofrancesco · June 26th, 2009, 08:21 PM

I used an online DOF calculator to generate numbers I posted, I was surprised it had 1/3" video camera in the choices. I assume most are no deeper than 15-20' so shooting at 2.2 would cover most of that depth (12.5'). When zoomed 2.2 is as wide as she goes.

I just wanted to confirm center, instead of the back. I was always curious about the dof. When I'm at the event its very difficult to see what is in and out of focus with the camera LCD.

June 26th, 2009, 01:48 PM	#1
Pete Cofrancesco Inner Circle Join Date: May 2004 Location: USA Posts: 2,995	Depth of Field I have been told when filming theatrical performances to manually focus on the back of the stage and everything in front of that point on the stage should be in focus. Seems to me focusing in the middle would give me dof to work with. I also ran a dof calculator and it says you have more dof behind the subject than in front. @50ft f/2.2 54mm = 5.5' in front / 7' behind subject.

June 26th, 2009, 02:39 PM	#3
John Estcourt Major Player Join Date: Oct 2007 Location: Scotland, Ayr www.amour weddingvideos.co.uk Posts: 305	I think the rule is 1/3 in front 2/3 behind for DOF I always set the focus before the start of a show, zooming in on the middle of the stage and setting that as my focus point. That should cover you except perhaps max zoom in low light when you may need to re focus due to the wide open iris. __________________ john estcourt www.amourweddingvideos.co.uk

June 26th, 2009, 08:21 PM	#4
Pete Cofrancesco Inner Circle Join Date: May 2004 Location: USA Posts: 2,995	I used an online DOF calculator to generate numbers I posted, I was surprised it had 1/3" video camera in the choices. I assume most are no deeper than 15-20' so shooting at 2.2 would cover most of that depth (12.5'). When zoomed 2.2 is as wide as she goes. I just wanted to confirm center, instead of the back. I was always curious about the dof. When I'm at the event its very difficult to see what is in and out of focus with the camera LCD.