Mailinglist Archives:
Infrared
Panorama
Photo-3D
Tech-3D
Sell-3D
MF3D

Notice
This mailinglist archive is frozen since May 2001, i.e. it will stay online but will not be updated.
<-- Date Index --> <-- Thread Index --> [Author Index]

P3D formats & focal lengths



Dr. T wrote:
>So, if I decide to mount my full frame stereo pairs from the RBT S1
>camera in half frame (4p)  mounts, have I magically transformed the
>fixed 35mm lenses of this camera to "a full frame equivalent" of 50mm?

Actually about 70mm. You have half the image. Similar to zooming in.

>How can the sheer size of the image affect the perspective of the lens?

>It is the viewing conditions that matter, not the size of the image.

You have less information in the image.

>For example, if Realist, full frame and half frame images are projected

>in the same show (using the same projector or equal magnification) then

>the Realist lens is still 35mm FL lens and, compared to the full frame
>stereo image taken with 35mm lenses, the Realist shows the same
>perspective, only smaller width.

The Realist shows the same perspective vertically as the full frame
image, but the full frame image will still show a wider perspective. In
effect, the Realist will project a normal image and the full frame will
project a wide angle image. The size of the image is not important. The
Realist image contains less information than the full frame. A
beamsplitter produces 1/2 the information on each image, similar to
doubling the focal length. IMHO
RDS