This is a simple thumb rule calculation used to determine the stereo base when you are using a non-standard camera lens separation in hyper/macro stereography. In order to achieve an optimum stereo depth, the separation of the camera lenses centers should be about one-thirtieth of the distance from the lenses that are closes to the subject in a scene. This rule works well under some optical conditions but not others, for example it works when the standard focal-length lenses are used. However, it usually needs to be varied when lenses with a longer or shorter than normal focal length are in use.
Open GL has grown to be the standard graphics API for scientific and CAD applications that are used today and it is very popular for consumer applications such as the world of PC gamin. OpenGL however, was originally created for the use on professional graphic workstations by Silicon Graphics Inc.
This is the idyllic distance and position for comfortable viewing of a stereo image.
An orthoscopic image is a stereoscopic image that is viewed with its planes of depth in a proper sequence. This is as opposed to a pseudo (or inverse) stereoscopic.
An orthostereoscopic image is an image that appears to perfectly spaced just as in the original view.
This kind of viewing is when the focal length of viewer’s lenses is equal to that of the focal length of the equipments lenses which the slides were viewed. It is said that this will allow you to view the objects as being the exact same size and with the same distance between each other within the viewer, just as in reality.
This format known as over and under involves using a mirror system in order to separate the two eyes images intended for the left and right eye that are situated on top of each other. Specialist mirror viewers are made for this over and under format.
With this over and under form of stereo recording or viewing, the left and right images are found to be positioned one above the other as opposed to side by side. They are viewed with the help of mirrors or prisms which will deflect the lights path to each eye as required.