Kodak Portra 100T

Portra 100T traces back to Vericolor VPL, the Kodak tungsten-balanced sheet film that interior and architectural photographers loaded for decades. Kodak replaced VPL with Ektacolor Pro Gold 100T in 1998, then folded that emulsion into the Portra brand a year later. The film was discontinued at the end of 2006 along with the rest of the slower professional tungsten stocks, as digital backs took over commercial interior work and demand collapsed.

The entire reason for this emulsion is shooting under 3200K tungsten and getting clean neutral color without filtering. Daylight films like Portra 160NC under tungsten go orange unless you load an 80A filter, which costs you two-thirds of a stop. With Portra 100T you set up your strobes off, your hot lights on, meter at box speed, and the negatives come back with whites that read white. For magazine interiors, advertising sets, and copy work, that workflow was the point.

Kodak built the film for exposure times from 1/1000 of a second up to 120 seconds with minimal color crossover, which is unusual for a color negative. Most C-41 stocks start drifting in color balance past a few seconds. Portra 100T held its tungsten balance across the full long-exposure range. Compared to Fujifilm NPL 160T, the Kodak ran slightly warmer in skin and slightly less green in fluorescent mixed lighting.

Available in 35mm, 120, and 4x5 / 8x10 sheets while in production. The sheet sizes were the heart of the market; very few people shot tungsten-balanced 35mm for any non-niche reason. Freezer stock from the final 2006 run still surfaces occasionally, and unlike E-6 reversal, expired C-41 ages relatively gracefully if kept cold. Expect a slight magenta shift and rate at ISO 80 to be safe.

Reciprocity exponent is 1.10. Zone Light Meter applies the correction past one second, so a metered 30-second interior reading lands near 35 seconds at the negative. For the long-exposure architectural work this film was built for, the math is gentle enough to trust without bracketing.