Agfachrome · ISO 64 Slide
Agfachrome 64
Agfachrome 64 was Agfa's flagship consumer slide film for the North American market through the late 1970s into the early 1980s. Production ran roughly 1974 to 1983. It was processed in AP-41, not E-6, and that is the central practical fact about any surviving roll: standard E-6 lines will not develop it. AP-41 is dead almost everywhere. A few specialty labs like Film Rescue International still run batches when orders justify mixing the chemistry.
The color palette is why collectors still talk about it. Agfa's ball-and-chain coupler chemistry produced what longtime Agfachrome shooters describe as pastel and honest, less saturated than Kodachrome 64 of the same era, less blue-biased than Ektachrome. A chateau on Kodachrome looks freshly painted. The same chateau on Agfachrome looks as it actually is. Greys clean, blacks deep, reds restrained to pinky rather than punchy.
The practical comparison is to Kodachrome 64, which dominated North America during the same years. Kodachrome won the market on punch and archival stability. Agfachrome won a smaller share on tonal honesty and the softer reversal curve that suited European overcast light.
For anyone holding cassettes today, the question is whether processing exists in your country. Cross-processing in C-41 will not give usable results because the dye couplers were engineered around AP-41's chemical reversal, not E-6's. Shoot it only if you have already lined up a lab. Otherwise the rolls are collectibles.
Thirty-five millimeter only. No 120, no sheets. The late-1970s packaging shows the orange and brown Agfa color scheme that any thrift-store film hunter learns to recognize at a distance.
Reciprocity exponent is 1.10, gentle for a slide stock. Zone Light Meter applies the correction past one second. A metered 5-second exposure becomes about 7 seconds at the negative. In practice you will rarely run Agfachrome 64 past a few seconds: the emulsion has been sitting around for forty years, and the dye stability has drifted in ways no math will fix.
How the app handles this stock
- Box speed: ISO 64. Picker exposes pull/push chips so you can shoot it at any speed you want and the meter follows.
- Reciprocity: Above one second the app raises metered time to the power of 1.10.
- Expired film: if you load an old roll, set the expiry year and storage in the app and the ISO scales for you. Slide decay rates are baked in.