The Stereo Window

An often confusing but important concept to understand when mounting stereo images is the Stereo Window. Any object (even the image frame itself) that exists in both left and right images holds a place in space from the viewer. Because of this, the most natural viewing experience is to have scene being viewed behind this virtual window created by the image frame. The "image frame" is the physical black box (Black in this example) that surrounds each image.

(Cross-Eye View Version)
Choose Parallel View Version
Whats the difference?

These are examples of setting the same images up for different window placement.
Watch the edges of the frames both on near subjects and far subject to see the differences.  Also try the Projection Simulation, which shows you what the images look like overlapped as if they were projected without you wearing your polarized glasses. Where they converge is where the stereo window is.

What you want to avoid is a "Window Violation". A window violation exists when objects which come in front of the window are cut off by the window.  This is a situation which cannot occur with a real window
and real objects. So avoid this When you want scenes to look natural.

R

L

Stereo Window set so that everything is behind the window
Projection Simulation (Click for pop-up)

 

R

L

Stereo Window set at infinity (everything in front of the window)
This is considered a "Window Violation". The people and the tank are cut off and hanging in space
Projection Simulation (Click for pop-up)
 

R

L

Stereo Window set in front of the presenter (the guy with the gun).
This is considered a "Window Violation". The people in front are cut off and are floating torsos.
Projection Simulation (Click for pop-up)

The general rule for mounting behind the window is the 3L Rule. You should see Less to the Left in the Left eye view.

A Through The Window Example will come soon.

 


Confused? Try Shab Levy's explanation of the Stereo Window
OR
http://stereomounting.com/window/
OR
Buy the The Stereo Window Tutorial Slide Set from Rocky Mountain Memories