Shallow to Deep focus possible in a scene? at DVinfo.net

Nick Popa · October 26th, 2010, 09:11 AM

Hey everyone,
I have a weird question... is it possible to go from a shallow DOF to a Deep DOF in one scene, almost like a rack focus but much more complicated.

I've never tried it, but giving it some thought it theoretically seems possible.... What if you.....
1. Start at a high fstop lets just say f16,
2. Go to your ycamera settings use the setting that slows down the change of the iris, so that when you turn it, it changes very smoothly.
3. In the settings, do the same thing with the gain, so that it changes slowly.
4 FINAL ...... Shoot the shoot at the high fstop, then open up the iris and bring the gain down

It may sound impossible to pull off, but would it work?
Are there any scenes in films that do do it, or is there a name for this shot?

Thanks!

Brian Drysdale · October 27th, 2010, 12:54 PM

In theory it's possible, although perhaps a DSLR camera with its moire issues and an OLPF intended for stills rather the video function (i.e the shallow DOF is being used to reduce this issue) mightn't be the best type of camera to do this.

It can happen with an in camera speed ramp, if the aperture is being adjusted when the frame rate changes. It could work if a character feels less isolated and becoming more aware of the world around them Like all effects, there has to be reason for doing it otherwise it just draws attention to itself..

Kin Lau · October 27th, 2010, 03:42 PM

On a DSLR, I would suggest using a manual focus lens that's been de-clicked with a smooth aperture, Leave the camera on auto-exposure or in the case of Canon DSLRs, use auto-ISO. Then just let the camera take care of the exposure while you handle the aperture. You'd pretty well want to use a lens that's no longer than the standard 50mm equiv. A 35mm or 50mm equiv FOV is likely the best focal length for this. You'd probably want a fast lens too.

October 26th, 2010, 09:11 AM	#1
Nick Popa Regular Crew Join Date: Mar 2010 Location: Flemington, NJ Posts: 120	Shallow to Deep focus possible in a scene? Hey everyone, I have a weird question... is it possible to go from a shallow DOF to a Deep DOF in one scene, almost like a rack focus but much more complicated. I've never tried it, but giving it some thought it theoretically seems possible.... What if you..... 1. Start at a high fstop lets just say f16, 2. Go to your ycamera settings use the setting that slows down the change of the iris, so that when you turn it, it changes very smoothly. 3. In the settings, do the same thing with the gain, so that it changes slowly. 4 FINAL ...... Shoot the shoot at the high fstop, then open up the iris and bring the gain down It may sound impossible to pull off, but would it work? Are there any scenes in films that do do it, or is there a name for this shot? Thanks!

October 27th, 2010, 12:54 PM	#2
Brian Drysdale Inner Circle Join Date: Feb 2006 Location: Belfast, UK Posts: 6,152	In theory it's possible, although perhaps a DSLR camera with its moire issues and an OLPF intended for stills rather the video function (i.e the shallow DOF is being used to reduce this issue) mightn't be the best type of camera to do this. It can happen with an in camera speed ramp, if the aperture is being adjusted when the frame rate changes. It could work if a character feels less isolated and becoming more aware of the world around them Like all effects, there has to be reason for doing it otherwise it just draws attention to itself..

October 27th, 2010, 03:42 PM	#3
Kin Lau Major Player Join Date: Mar 2009 Location: Ottawa, ON Posts: 385	On a DSLR, I would suggest using a manual focus lens that's been de-clicked with a smooth aperture, Leave the camera on auto-exposure or in the case of Canon DSLRs, use auto-ISO. Then just let the camera take care of the exposure while you handle the aperture. You'd pretty well want to use a lens that's no longer than the standard 50mm equiv. A 35mm or 50mm equiv FOV is likely the best focal length for this. You'd probably want a fast lens too.