View Full Version : AE Shift = Depth Of Field Tweaker?


Stephen Finton
June 28th, 2005, 05:16 PM
I turned my HC1000 on AUTO EXPOSURE and went into the AE SHIFT menu and took it down to its limit, -4.

Now, I seem to be getting a shallower DOF! It's darker, so I think it is using the ND filters to widen the iris beyond its sweet spot!

Kick Ass!

Stephen Finton
June 28th, 2005, 05:41 PM
Nope!

Just my imagination. I did not whitness the ND filters flipping. All it does is put a limit to the AE.

Tom Hardwick
June 29th, 2005, 10:17 AM
Moving the AE shift down to -4 means that instead of the camera shooting (in automatic exposure mode) af f/4 (say) it'll now shoot at f/8 ~ though it depends how much under-exposure Sony have programmed in for each 'click'.

So contrary to what you've observed Steven, you'll actually have increased the depth of field - as well as making your shots darker of course. Thing is that the camera won't want to use f/8, it'll just put more and more ND into the optical path, so your dof will most probably remain unchanged.

tom.

Stephen Finton
June 29th, 2005, 10:53 AM
Moving the AE shift down to -4 means that instead of the camera shooting (in automatic exposure mode) af f/4 (say) it'll now shoot at f/8 ~ though it depends how much under-exposure Sony have programmed in for each 'click'.

So contrary to what you've observed Steven, you'll actually have increased the depth of field - as well as making your shots darker of course. Thing is that the camera won't want to use f/8, it'll just put more and more ND into the optical path, so your dof will most probably remain unchanged.

tom.

But wouldn't an ND filter make the iris open more when the camera is in auto exposure? I thought I read that somewhere...

Juan Parra
June 29th, 2005, 11:36 AM
But wouldn't an ND filter make the iris open more when the camera is in auto exposure? I thought I read that somewhere...

Think of an ND filter as a light attenuator that will help you get the right exposure.

To get a narrow DoF

Pull the camera back, zoom in and open the iris all the way (smallest number, i.e. f1.4).

The farther back the camera is from the subject while maintaining the composition and exposure you want, combined with zooming all-the-way into the subject, having the iris as wide open as possible, will give you the narrowest DoF.

In order to have the iris wide open and the correct exposure when you are outdoors, or when it's too bright, you'll need ND filters or increase the shutter speed (i.e. 1/120-1/10000)

Note: Be mindful when upping the shutter speed to reduce light coming into the camera, and you have a moving subject, since that subject might look jerky when played at normal 60i or 24p.

Stephen Finton
June 29th, 2005, 01:43 PM
Think of an ND filter as a light attenuator that will help you get the right exposure.

To get a narrow DoF

Pull the camera back, zoom in and open the iris all the way (smallest number, i.e. f1.4).

The farther back the camera is from the subject while maintaining the composition and exposure you want, combined with zooming all-the-way into the subject, having the iris as wide open as possible, will give you the narrowest DoF.

In order to have the iris wide open and the correct exposure when you are outdoors, or when it's too bright, you'll need ND filters or increase the shutter speed (i.e. 1/120-1/10000)

Note: Be mindful when upping the shutter speed to reduce light coming into the camera, and you have a moving subject, since that subject might look jerky when played at normal 60i or 24p.

Yeah, I know about the zoom trick. And I won't use higher shutter speeds unless I need to synch with a computer monitor, though I am more likely to turn down the refresh rate on the computer before I'll subject the video to a higher shutter speed. I guess if it is a dividend of 60, I'd be okay.