HD Depth of Field

[Landon D. Parks]

Ok, I was watching Once Upon a time in mexico again, and at second look, some of the scenes looked like they had a VERY shallow depth of field.

 

Now, I though HD could not get that shallow of a depth without a PRO35 Adapter? Or was that even depth of field i seen. Someone onnce said you could just "Pull the background out of focus" to get an effect like depth of field..

 

Im lost. need some help. :(

[David Mullen ASC]

You can get a shallower-focus look in HD with a longer lens and shooting wide-open (or nearly), or focusing close to the lens. You just can't get one shooting on wider-angle lenses in medium shots.

 

Just think of it this way -- in terms of depth of field, shooting in HD is like shooting in 35mm with the lens stopped down by 2 1/2 stops. That's it. This is not rocket science; it's just basic photography.

 

So if you're shooting a close-up in HD at T/2.0, it's like shooting in 35mm at T/4.0-5.6 split, which will still give you an out-of-focus background. It's just in the medium shots and wider-angle shots where it's harder to reduce depth of field to 35mm levels. I was just looking at an HD feature I shot, with a lot of people at a dinner table in a row. Some shots were made with the camera closer on a wide-angle lens and the whole row is in-focus even though I was shooting at T/2.8 -- but other shots were made with longer lenses and in the close-ups, the depth of field looks shallow.

 

HD just has more depth of field ON AVERAGE compared to 35mm, but it doesn't mean you can't use the traditional tricks to lower depth of field -- it's just harder, not impossible. This is one reason for using the Zeiss Digi-Primes; with a lens that can open to T/1.6, you can get the depth of field characteristics of shooting in 35mm at around a T/2.8-4.0 split.

 

The question is whether it is absolutely important to have a shallow-focus look. Back in the 1950's when cinematographers were striving to shoot at T/5.6 if possible for better depth of field, they probably would not have complained about the depth of field of HD.

 

A shallow-focus look has become more popular over time for color photography because it is essentially "prettier" -- color is another layer of information in the frame and it can become distracting if too much of the frame is in-focus, unless the color is carefully controlled. This is one reason why the few deeper-focus color movies tend to be given a monochromatic design. But on a lower-budget film or a film shot on real locations, that degree of color control is hard to achieve and being able to simply throw the background out of focus is a big advantage.