Stereoscopic technique using overlaid color channels—typically red/cyan—to create 3D without special displays. Cost-effective but suffers from color shift and limited depth perception.
Red and cyan overlaid on a screen — that's the core idea, and it actually works, though most modern productions have long since moved past it. For decades, anaglyph was the cheapest way to create stereoscopic 3D, especially in the cinemas of the 1950s and then again in the 2000s when the 3D hype emerged. The viewer wears glasses with colored lenses — one red, one cyan — and their brain separates the two image planes. Theoretically elegant. In practice, a compromise that is only accepted in niche projects today.
The technical reality: You need two identical cameras or a camera with a beam splitter, positioned at eye distance from each other. Each captures a perspective. In editing or during capture, you combine the two recordings so that one is placed in the red channel, the other in the cyan channel (blue + green). The overlapping image areas then create the spatial perception — the brain processes the color contrast as depth. Sounds simple, but it's prone to issues: any misalignment, any focus error leads to ghosting, i.e., double images or color fringing around objects.
The real price is cosmetic. Anaglyph brutally distorts colors — red areas appear more dominant, cyan-toned zones lose saturation. A skin-toned face becomes a pink-green masquerade. That was acceptable in early drive-in movies; today, no producer would let it pass, unless the look is intentional (retro pastiche, low-budget aesthetic). Furthermore, the depth effect is flat — you don't get the subtle gradations of modern stereoscopic methods like polarized cinema or active shutter glasses.
Where it's still found: Scientific visualizations, YouTube videos in anaglyph 3D format, artistic experimental films that deliberately play with retro aesthetics. Also still common in 3D comic printing. For television or cinema, however: obsolete. Even with ultra-low-budget productions, filmmakers prefer to use polarizing filter systems or side-by-side compositions.
The lesson for modern stereoscopy: Anaglyph shows why specialized hardware is sensible despite higher costs. The uncompressed loss of quality is simply too great.