Filmmakers are constantly competing for viewers' attention. In this case, the stake is placed not only on the plot, famous actors, special effects, but also on the maximum realism of perception.
Anaglyph technology
Anaglyph is a method of obtaining a stereo effect by color coding images, invented over a century ago. In such films, two color filters are imposed on the picture for both eyes, and in special anaglyph glasses for viewing, instead of glasses with diopters, there are also special light filters, due to the presence of which each eye sees its own picture. For the right eye the filter is blue / cyan, for the left - red.
Thus, each eye perceives the image in a color corresponding to the color of the filter of the anaglyph glasses. And volumetric perception is achieved due to the presence of a slight difference in perspective between the images captured by the right and left eyes, and despite the fact that each eye sees only part of the spectrum, the properties of the brain allow a person to perceive the image as a whole as full color.
The anaglyph viewing method is the simplest, cheapest and most popular way to view 3D films and images, since nothing more is required besides special glasses.
But this method also has disadvantages: incomplete color rendition, rapid eye fatigue, visual splitting of the picture and contours, difficulties in viewing compressed video. After using anaglyph glasses, a person for some time has a feeling of discomfort in the visual perception of the real world and a decrease in the color sensitivity of the eyes.
Anaglyph films can only be watched with stereo glasses, whose filters match the parameters of the given film (for example, sometimes there is a red filter for the right eye). On a stereo player, such a movie will run as usual.
3D movies
Unlike anaglyph films, in 3D, images are alternately projected onto the screen for one or the other eye, which often replace each other. So, on a 3D TV screen with a refresh rate of 120 hertz, the image for each eye appears 60 times per second. To watch 3D films, in addition to a 3D TV, you also need additional equipment.
If you are watching 3D movies on your home 3D TV using shutter glasses, one picture is displayed at a time for one eye, the one whose shutter is open at the moment. IMAX 3D cinemas have special equipment and 3D images are created with polarized beams.
Until 2009, when Avatar was released in 3D, most of the films advertised as 3D were actually created using anaglyph technology.
The color rendition of 3D films is better than that of the old anaglyph cinema. We can say that 3D technology has replaced anaglyph.
