Agfacolor CT 100

Agfacolor CT 100 is the original 1984 daylight slide film that anchored Agfa's E-6 line for over a decade before evolving through CT100i and CT100x into CT Precisa around 1998. CT stood for Color Transparency; the 100 marked daylight balance at ISO 100. For most of the late 1980s it sat alongside Kodachrome 64 and Fujichrome 100 as one of the three serious consumer slide options in European camera shops.

The character is honest more than spectacular. Color neutrality rather than the punched-up saturation Velvia introduced in 1990, with fine grain measured at RMS 8 on Agfa's published data and high sharpness that held up to projection at meaningful screen sizes. Skin tones came back without the warm push Kodachrome built in by design; landscapes rendered closer to what your eye saw than what Velvia would make them. Reviewers of the period compared its palette to Fujichrome 100 RD rather than to the Kodak chromes.

Latitude for slide film was decent. Agfa rated it for processing at minus half a stop to plus two stops, EI 70 to EI 400, which is wider push range than most E-6 stocks of the era. That made CT 100 quietly useful for stage and concert work where metering went off-script. For landscape at box speed the curve held a long highlight shoulder.

The film survived in this nomenclature through several reformulations. Photographers who shot it through the 1990s cannot agree on whether the 1989 or 1994 batches were sharper, partly because Agfa revised the emulsion incrementally without renaming.

Available historically in 35mm 36-exposure cassettes. Sheet sizes were never offered for the CT designation. Production transitioned to CT Precisa by 1999, and the freezer-stock circulating today is mostly from the late 1990s runs.

Reciprocity exponent is 1.10. Zone Light Meter applies the correction past one second, so a metered 30-second exposure becomes about 35 seconds at the negative. For most slide work outdoors the threshold rarely matters; for night and cross-processing shots, the gentle correction holds.