Ilford XP1 400

Ilford launched XP1 at Photokina in September 1980 and put it on shelves in January 1981, claiming the first chromogenic black and white film. The trick was building dye couplers into the emulsion the way C-41 color negative does, then running the whole thing through standard color minilab chemistry. The silver gets bleached out at the end. What you scan or print is pure dye, like a desaturated color negative.

That structural choice changed how the film looked. Grain comes from dye clouds rather than silver crystals, which means it gets smoother in dense highlights and slightly more textured in shadows. The opposite of every silver film. Wedding shooters in the mid-eighties loaded XP1 specifically for that highlight smoothness, because a white dress photographed on XP1 held tone where Tri-X or HP5 would compress to paper white.

Ilford recommended their proprietary XP1 developer for best results, and that chemistry has been gone for decades. C-41 worked then and still works on the rare frozen roll that turns up today. Expect lower contrast on expired stock; labs sometimes add a half-stop push to compensate. The other advantage chromogenic films share with color negatives is that infrared dust and scratch removal in scanners works on them, where it cannot on silver-based black and white.

XP1 ran until 1993, when XP2 replaced it. XP2 was itself replaced by XP2 Super, which is still in Ilford's catalog and remains the only chromogenic black and white film on the market. If you want this look fresh, XP2 Super is the only path. XP1 itself is freezer-stock only now.

Reciprocity exponent is 1.31, which matches the modern XP2 Super published curve. Zone Light Meter applies the correction past one second. A 30-second meter reading lands at roughly 90 seconds at the negative. With dye-based films the contrast also stretches under long exposure, so consider pulling development a touch if you are committing to a tripod scene over a minute.