Buried inside a routine 1966 CIA Research & Development Catalog Form — the kind of dry, mimeographed budget paperwork that filled Langley's filing cabinets — sits a reference to a color reproduction technology that has almost entirely vanished from public memory: Electrocolor.

The form describes a study, budgeted for fiscal year 1967, aimed at "Evaluation and determination of potential improvements of present electrocolor system." The document lays out why the National Photographic Interpretation Center (NPIC) cared:

The electrocolor process shows potential for producing color reflection prints for exploitation use. Its unique characteristic of individual color contrast control of the three basic colors, red, green and blue, indicates that this product would be extremely usef[ul]...

And earlier in the form:

The increasing use of color reconnaissance photography necessitates thorough investigation of all color reproduction systems to determine those advantages which can be applied to Center requirements.

The categories of effort listed are telling: "Electrocolor Plating — Materials — Equipment — Reproduction Techniques and Materials." This wasn't ordinary chemical dye-transfer printing. Electrocolor was an electrochemical process — sometimes called electrolytic color anodizing — in which colors were deposited into a porous, anodized metal surface (typically aluminum) via electrical current controlling the migration of metal salts into the pores. The color wasn't a dye layer on top; it was inside the oxide.

What made it attractive for spy photography was exactly what the CIA form flags: independent, granular contrast control over each of the three primaries. In an era when a U-2 or CORONA satellite might return a canister of color negative that had to be interpreted for a general's briefing the next morning, a print process that let an analyst pull green foliage down while pushing red vehicle paint up was genuinely valuable.

So where did it go? A few threads survived:

• Electrolytic coloring of anodized aluminum is still the industry standard for architectural window frames — those bronze, black, and champagne facades on 1970s office buildings are electrocolor.
• The photographic version, however, was essentially outcompeted by improvements in dye-coupler chromogenic prints (Kodak's Ektacolor, later inkjet), and by the digital revolution that made per-channel contrast control a slider rather than a chemistry problem.

The modern parallel is striking: what a 1966 CIA contractor was trying to build with plated metals and electrical current is now the "Curves" tool in Photoshop, or the per-channel tone mapping in Lightroom. Every phone photographer casually adjusts red, green, and blue contrast independently — a capability that once required a classified R&D program.

The document is also a reminder that Cold War intelligence quietly bankrolled a huge amount of imaging science. The National Photographic Interpretation Center's need to squeeze more information out of a frame of film drove real chemistry, real optics, and real engineering — most of which was declassified only decades later, by which time the digital sensor had made the underlying problem obsolete.