History of Anaglyphs It was W. Rollman who in 1853 first illustrated the principle of the anaglyph using blue and red lines on a black field with red and blue glasses to perceive the effect, but this was for line drawings only. In 1858 Joseph D'Almeida began projecting three-dimensional magic lantern slide shows using red and green filters with the audience wearing red and green goggles. It is to Louis Ducas du Hauron that we owe the first printed anaglyphs, produced in 1891. This process consisted of printing the two negatives which form a stereoscopic photograph on to the same paper, one in blue (or green), one in red. The viewer would then use coloured glasses with red (for the left eye) and blue or green (right eye). The left eye would see the blue image which would appear black, whilst it would not see the red; similarly the right eye would see the red image, this registering as black. Thus a three dimensional image would result. William Friese-Green created the first three-dimensional anaglyphic motion pictures in 1889, which had public exhibition in 1893. 3-D films enjoyed something of a boom in the 1920s. The term "3-D" was coined in the 1950's. As late as 1954 films such as "The Creature from the Black Lagoon" were very successful. In 1953, the anaglyph had begun appearing in newspapers, magazines and comic books. The 3-D comic books were one of the most interesting applications of anaglyph to printing. Over the years, anaglyphic pictures have sporadically appeared in comics and magazine ads. Jaws 3-D was a box-office success in 1983. At present the excellent quality of computer displays and user-friendly stereo-editing programs offer new and exciting possibilities for experimenting with anaglyph stereo.
Why do I prefer ANAGLYPHS?
Because their size is unlimited and it is the easiest way to look at stereo's for almost everybody (problems here though for some color-blind people). Don't expect people to learn 'parallel focussing' or 'cross eyed viewing' in a few minutes. Anaglyphs have immediate effect, the lack of color may be compensated by showing the original colour-rendering.
A few tips on making anaglyphs
NB. By convention the LEFT GLASS of your anaglyph glasses is RED. Sometimes however anaglyphs on the internet are mirrored and you have to use the blue-green as left glass.
-Making the first (right) image :
Adjust the lens length setting of the camera to 100mm.
Make a render with enough decor in it : foreground, middlesection, background and make the viewing angle small, as if you are in front of the scene (a top view in stereo doesn't make sense). Save the render as right image .
-Now for the second (left) image :
Rotate the whole scene (including backgrounds, floor, lights) one degree around a vertical axis in front of the scene, either directly in front or from a small distance (fig.1). Positive rotation (+1°) will deliver the left image. Shifting the virtual camera to the left will have the same effect (theoretically), but the amount of shift is difficult to define as an exact value and the small difference in camera angle is not taken into account, resulting in unacceptable separation between right and left in the anaglyph. Save the render as left image.
Perspective view Top view Anaglyph stereo
The black cross marks the rotation point
Important: the rotation angle is more or less dependent on the the lens length. A rotation of 1° will be sufficient for a 100mm lens while a 50mm lens needs at least 2°. Bigger rotation angles however also give more divergence, which may lead to noticable ghosting. Therefore a 100mm lens with 1° rotation is recommended.
-If you want objects sticking out of the stereo-window towards you (protrusion effect), then the rotation axis should be placed a little bit into the scene. This is actually incorrect stereo (righ and left are reversed in the foreground) but it delivers the well-known spectacular effect.
-Transformation of colored computer graphics images to shades of gray is recommended. Colors (especially green and red) may give wrong interaction with the colors of the glasses. Sometimes however blue and yellow will work out well. Some anaglyphprograms can filter out disturbing colors.
- Now import left and right images into the anaglyph program. Usually the positioning of left and right will be correct. Nevertheless you can use program tools to shift the overlapping images untill the stereo is comfortable to the eyes. Remember that foreground objects should coincide for optimal viewing. You can enhance the protrusion effect however by shifting the images a little bit apart. You will notice the diverging separation of right and left image from near-point to the infinity point.
-Anaglyphs best can be looked at a distance of about 50-80cm from the screen.
-Anaglyphs glasses and programs
Many bookstores or toy shops sell books with anaglyph images, including anaglyph glasses.
My favorite anaglyph program is Stereo Photo Maker which is a very comprehensive stereo-editor. It also can batch-convert stereopairs into anaglyphs.
Making separated stereo pairs
I can keep this very short. Instead of blending the images with the anaglyph program, you now place them next to each other. You might follow this procedure (Microsoft Photo Editor):
-create an empty bitmap base with New
-load© left image , paste it onto the bitmap base.
-load© right image, paste it onto the bitmap base and drag it next to te left image .
-select/copy the stereo-pair, and paste/save it as new .
-now resize the image; for parallel viewing the pair should be not wider then 2x7cm.
Stereo Photo Maker can handle this kind of procedures more elegantly.