Kodak PR-10 Instant

Kodak shipped PR-10 in April 1976, the integral instant film that ran inside the EK-4 and EK-6 cameras and broke the Polaroid monopoly on the format for nine years. Ten exposures per pack, ISO 160 on later cassettes (some early labels said 150), and the clever trick of being exposed from the back of the print rather than the front. That detail mattered. Polaroid's SX-70 design had to reflect the image through an internal mirror. Kodak skipped the mirror entirely. The result was a simpler camera and sharper images because light traveled through fewer layers to the negative.

Two finishes existed. Standard PR-10 had a glossy surface. PR-10 Satinluxe came with a silky matte finish for people who preferred reduced glare. Same emulsion underneath. The Kodamatic line that arrived in 1982 brought a faster 320 ISO HS 144-10 stock and a tweaked pack shape.

Polaroid filed suit the same month PR-10 went on sale. The case ran for nine years. In 1985, Judge Rya Zobel of the District of Massachusetts ruled Kodak had infringed seven Polaroid patents and ordered the entire Kodak instant business shut down. Kodak announced discontinuation on January 9, 1986. The damages litigation continued for six more years before the court awarded Polaroid roughly $925 million in 1991, which remains one of the largest patent judgments in American photography history.

What it looked like. Saturation ran lower than SX-70 with a slightly cooler base. Skin tones rendered acceptably but not as warmly as Polaroid users were used to. Resolution was higher; the back-exposure design paid off in detail at the cost of color punch. Compared with later Polaroid Spectra, PR-10 sits closer in feel to early SX-70 with more clinical neutrality.

The film is irreplaceable. No third party has ever manufactured a compatible cartridge. Surviving packs from the 1976 to 1986 production years are past usable and develop with severe color shifts or fail entirely. The cameras are display objects now.

Reciprocity exponent is 1.0. No correction is needed past one second; metered time equals shot time. Zone Light Meter still applies the calculation past the threshold for consistency, but the correction is mathematically a no-op.