35mm DOF Machine

[Colin Pritchett]

Hi all,
First post here on DVi and after reading alot of posts and having come from photography originally I have a question...What is a 35mm DOF Machine? I understand DOF and the relationship between focal length and aperture but do not understand the term and how increasing? DOF is possible via a contraption (machine) with video. I have just received my new (to me) GL2 with Canon W/A lens, shotgun mic, and video light and am currently deciding on my first subject for a documentary film. I have shot a few shorts of family in frame mode and am using Sony Vegas 8 for editing. Thanks for any responses.

Colin

[Bob Hart]

Have a look at Special Interest Areas, then Alternative Imaging Methods and you'll find out all about it.

The device you describe interposes between a 35mm stills or cine lens and the video camera to enable that camera to see the world as if it were a 35mm film camera with a 24mm wide sensor than the 1/3" sensor that is most commonly found in home video cameras.

It enables the creative use of selective focus you are accustomed as a stills photographer and the framings and perspectives you expect from your stills lenses.

Significant products are :-

P+S Technik Mini35 and Pro35, more or less regarded as the benchmark.
Movietube, which uses a wax screen (somewhat like the Boss screen of plate cameras).

then the more well known of the alternative products which largely evolved by participants at this site.

Redrock M2
Letus
Brevis
SGPro (soon to be released "Blade")

If you use the search function on this site, look for Agus Casse, who set the whole alternative adaptor thing off when he made one for about US$20-00 I think in Guatamala out of a clear CD-R disk, a CD spindle motor, a CD-R retail case and a salvaged stills cam.

[Don Palomaki]

Essentially the video camera ends up taking a macro image off a ground glass (usually moving to hide its grain). The ground glass image is formed by a 35mm lens and thus has the DOF characteristics of the 35mm lens.