A short introduction to the basic
knowledge for stereoscopic 3D recording
How does 3D
work ?
To be able to see spatial, human beings have binocular vision. Each eye sees the environment with a slight difference in perspective; the so called parallax. The brain uses these two slight different views to generate a spatial impression
How is 3D recorded
?
To deliver the two views with that slight difference in perspective, a scene must be recorded with two cameras instead of the eyes. These cameras are synchronized and record that scene from two different perspectives; the distance between these positions is called interaxial.
To be able to see a movie in 3D, the left eye needs to get the view of the left camera and the right eye the view of the right camera. The brain is then able to combine these two images to a single three dimensional image.
How do
3D Rigs work ?
For three dimensional recording a special rig for the cameras is needed. Generally there are two kinds of3D rigs:
.
Side-by-side Rigs carry two cameras next to each
other. To
create a three dimensional effect in a very
wide shot you need
the wide interaxial distance they
can provide. Side-by-side rigs
are ideal for panoramic
and
aerial shots,
but close-up and detail
shots can
hardly be achieved as
most high resolution cameras
are too large to
be setup
very close together.
Mirror Rigs like the Standard Rig and the freestyle Rig from P+S TECHNIK allow overlapping
the images of both cameras regardless the size of cameras to
achieve very narrow interaxial distances for perfectly beautiful
close-up and detail shots. The mirror box setup is the base for the Universal Mirror Rig
as well as for the very lightweight and easy-to-balance
P+S TECHNIK Freestyle Rig.
Basic techniques to influence
a 3d-picture
By variatio
n of the interaxial, the depth of the 3D-picture can be adopted. This is necessary, to prevent too large interaxials. These would cause headaches and discomfort to the viewers.