Kodak Tri-X 400

Original (research-derived). See the notes, the B&W README, and the Knowledge base.

The film

Kodak Tri-X 400 is the most iconic B&W film in history, the stock of classic photojournalism and street photography. Its signature is dark, rich contrast, deep blacks, a wide tonal range, and a heavy, distinctive (love-it-or-hate-it) grain, with huge exposure latitude and legendary push tolerance.

The look in one line

Gritty, high-contrast, deep-black reportage B&W with heavy characterful grain and mid-tone bite.

How it's built

• Acros+Ye base: Acros gives the richest tonality; the yellow filter adds Tri-X's slight contrast and darker skies.
• — + Highlight —+ Shadow —: punchy contrast with deep rich blacks (Tri-X renders greys darker and blacks deeper than HP5).
• Grain —, —: the heavy, clumpy Tri-X grain.
• Clarity —: the important move: Tri-X's tactile, gritty mid-tone bite. This overrides the Clarity—default because faithfulness demands it (Tri-X without grit isn't Tri-X).
• High ISO: pushes the grain and grit; Tri-X lives at 400—+.

Datasheet confirmation & an honest nuance (Kodak F-4017, fetched & extracted)

The F-4017 datasheet confirms: fine grain for its speed, wide exposure latitude, "rich tonality", and a development aim of contrast index 0.56 (i.e. box-speed Tri-X, normally developed, is actually moderate contrast). The sheet also documents that pushing raises contrast and graininess and sinks shadow detail, which is exactly the point: the iconic "Tri-X look" (deep blacks, heavy grit) is substantially a product of push-processing and printing choices, not the base curve.

Design decision (documented honestly): this recipe targets the iconic pushed/reportage rendering, the Tri-X people mean when they say "Tri-X", not box-speed-normal-dev. Hence Shadow —/ Highlight —/ Clarity —/ —-— grain / high ISO. A faithful box-speed variant would be: —, Shadow —, Clarity —, Grain —/—, ISO ≤ 1600.

Validation tier

Datasheet (extracted) + characteristic. Scan-fetch pending: open sources (Wikimedia) lacked accessible Tri-X pictorials this pass; drop a Tri-X reference PDF into _reference-sources/ or references/ to reach the full scan tier (the Gold 200 workflow).

vs the other B&W originals

• Acros 100: the clean/fine opposite. Smooth, fine grain, —.
• HP5 Plus 400: the middle ground, even grain, balanced contrast, deep-but-natural shadows, —. Tri-X is grittier and more contrasty than HP5.