Depth of Focus


I have a 6 foot camera crane (or jib… not quite sure of which term to use here). The photo shows the crane with the Sony camera mounted at one end and a monitor and counter weights down at the other end. The lens was made by Topcor over 50 years ago. My father used it with his full frame, 35mm SLR still camera.  It’s mounted on the Sony camera via an adapter.

Topcon RE Auto-Topcor Lens, 25mm

I set up a small test still life and shot a few test shots. The best of the bunch is presented below. The camera was 21 inches from the subjects, the aperture was f5 and shutter speed 1/60th of a second. It appears that the camera is moving straight up and down. That’s the benefit of a crane; the camera is not still and panning but is actually following the subjects. At this close range there is an interesting circular swaying at the camera end of the crane. I could not eliminate it. I used the same crane for a few shots in Nudged and that swaying was not apparent.  Those shots were of objects farther away and entailed bigger movements of the crane, so the swaying was not obvious.

I’ve been wondering how to illustrate the title in a logo. The photo above, which is in-focus in the center and out-of-focus on front edge of the lens and the back of the camera, illustrates depth of field. Depth of focus applies to where the image is in focus, inside the camera, behind the lens. So, that illustration still eludes me. A final logo is still in the future.

The Bronica medium format camera will be used by Barbara in the film. In an early scene, Barbara and her sister, Maureen, talk about how the camera was converted from film to digital by replacing the film cartridge on the back with a big digital sensor. One concern of such a conversion is: Will the lens focus on the sensor? This is where depth of focus is important. Too geeky?

The film is about the ways in which people envision their lives through dreams and how those dreams often may not be in focus with reality. We explored that theme somewhat with the character of Rusty in Nudged. In the new film, every character will be examined both in their dreams and in what passes for reality.

The photograph was taken using the photo mode of my Sony digital cinema camera with a Zeiss Distagon ZF.2 28mm Lens (60th of a second, f2.0, and ISO 1000).

Depth of Focus is a photography term.  Two of the characters use cameras. Maureen, the middle sister, is a documentary filmmaker and Barbara, the youngest, is a still photographer.  For each of them, we have a unique camera.

Maureen uses a Sony DSR-PDX10 DVCAM camera. This is the camera we shot Impasse with, it was used as the TV studio camera in Nudged, and it returns again as a prop in the new film. Maureen will use the camera during interviews employing a method developed by Jennifer Fox called “passing the camera.” During an interview the subject and the filmmaker pass the camera back and forth. The camera has two microphones so both parties can speak and be recorded.

The method is explained in this article from Documentary Magazine, “The  ‘passing the camera’ technique becomes the great equalizer, as no one person in the conversation has more power than the other. Both film each other, both can ask questions of the other, both people are equally on the line. “On top of that,” Fox adds, “the whole question, ‘Can a layperson shoot with a camera?’ is so obviously answered in the film. My camera instruction to each woman took about 30 seconds, and within 30 seconds they were filming me, often quite beautifully.”

Barbara uses a Bronica ETRS medium format film camera that was made in the 1980’s. The film used in this camera is 2 inches wide and the resulting image is huge and detailed. Barbara’s camera has been converted to use a digital chip rather than film. This makes it more practical for modern photography.

There are several ways to convert the ETRS camera to digital recording, Jeff Bauers describes one approach. Barbara’s camera conversion is simpler than what is shown in the article and practically indistinguishable from the film version.

A lens focuses light to form an image behind the lens. This image is “in focus” not at a point but across a small distance. The image is out-of-focus in-front of and beyond this space.

The small diagram below illustrates three aspects of lenses: Depth of Focus, Depth of Field and Circle of Confusion.

diagram-depth-of-focus

For the new movie, the title relates to how the characters see the world in their minds. Each of us sees the world through a “lens” of our beliefs, superstitions, fears and joys.  How the character’s individual “lenses” process the events of the story, determines the clarity with which they see and the width of their in-focus space determines the breadth of their understanding. The characters see some things clearly and other things distorted.  The out-of-focus parts lead to conflicts and confusion.

The Circle of Confusion relates somehow too but at the moment the only confusion lies in the screen writer’s mind.

girl-hareThe new film will work on a number of levels: current time, flashbacks and dreams. For the dreams I’ve been exploring Celtic myths and characters from Irish & Celtic history and traditions. One such story is the hare and the hunter.

In this story a hunter shoots at a hare wounding it. The hare runs off and the hunter follows it into a cave. In the cave the hunter finds a beautiful girl on a throne with a wound in the same place as the hare.

This story, a bit elaborated upon, will be part of a flashback (a mother reading a story book to her son), part of a dream by the grown son and part of the current time of the story.

Dianne is creating the actual book that the mother will be reading. A rough sketch of the girl and the hare are on the right.