Kodak Tri-X 400

Overview

Kodak Tri-X 400 is the oldest continuously-produced black-and-white film in the world and the most-shot fast B&W film in photographic history. Kodak introduced Tri-X in 1954, and despite multiple reformulations over seven decades, it remains the benchmark for fast cubic-grain B&W film. Tri-X defined the aesthetic of mid-20th-century photojournalism (Robert Frank's The Americans, Eugene Smith's Pittsburgh project), street photography (Garry Winogrand, Diane Arbus), and continues to dominate contemporary documentary and fine-art B&W work.^[1]

Historical context

• 1954 — Tri-X 400 introduced. Original formulation rated at EI 400 with the newly-standardized ASA/ISO scale.
• 1970s–1990s — Multiple minor reformulations refining grain structure and spectral response while preserving the core Tri-X character.
• 2007 — "New Tri-X 400" (Kodak's formulation refresh). Marginally finer grain than older formulations; tonality preserved. Current production stock dates from this revision.
• 2013–2026 — Kodak Alaris (a British spinoff formed after Eastman Kodak's 2012 bankruptcy reorganization) handled distribution; manufacture remained at Eastman Kodak's Rochester, NY plant throughout.
• Present (since Jan 2026) — Eastman Kodak resumed direct distribution of Tri-X 400 alongside several other emulsions (Gold 200, UltraMax 400, Ektar 100, Ektachrome E100). Current-production packaging features the iconic red-and-yellow "K" Kodak logo, distinct from the Alaris-era "Kodak Professional" yellow wordmark. Available in 35mm, 120, 4×5, and 8×10 formats — one of the few remaining fast B&W films offered in sheet film.

The film's 70+ year continuous production is unmatched — no other current B&W stock has a comparable history.

Design philosophy — classic cubic grain

Tri-X uses Kodak's traditional cubic-grain emulsion technology (distinct from their newer T-grain tabular-crystal structure used in T-Max). Practical implications:

• Grain: visible and "character-building" — Tri-X grain is a feature, not a defect. Photographers choose Tri-X specifically for its grain texture at moderate enlargements.
• Forgiving latitude: ±2 stops exposure tolerance without visible quality loss. One of the most forgiving B&W films ever made.
• Warm tonal bias: shadows render with warm undertones (a Kodak-family trait); highlights bloom slightly
• Response curve: gentle S-shape; moderate contrast at box-speed development

Exposure characteristics

Tri-X 400's rated box speed is EI 400, but the film's practical behavior varies by photographer's preference:

• EI 400 (box) — honest box-speed delivery; optimal for average-contrast scenes
• EI 320 — common "pictorial" rating; 1/3-stop overexposure produces slightly richer midtones and shadow detail
• EI 250 — more aggressive overexposure for fine-art B&W work; develop at box time
• EI 800–3200 — push territory; see Push Processing section below

Many photographers consider EI 320 the "true" Tri-X speed for pictorial work — the film delivers optimal mid-tone rendering at this slightly overexposed rating.

Push processing — the canonical push film

Tri-X 400 is THE canonical push film — the example cited in virtually every push-processing discussion. Behavior:

• EI 800 (+1 push) — clean; minor grain increase, maintained shadow detail
• EI 1600 (+2 push) — classic street/documentary push register; Garry Winogrand's standard rating. Noticeable grain, some shadow compression, dramatic contrast
• EI 3200 (+3 push) — usable but heavy grain; shadow detail significantly compromised. Daido Moriyama's signature aesthetic uses Tri-X at EI 3200 or higher
• Beyond EI 3200 — gritty, high-contrast territory; practical ceiling for most photographers

See Push Processing for the general theory.

Development workflows

Tri-X is exceptionally accommodating across developers:

• Kodak D-76 1:1 — the classic pairing; 9:30 at 68°F for EI 400. Reliable, reproducible, moderate grain.
• Kodak HC-110 Dilution B — 5:45 at 68°F; convenient (one-shot concentrate, long shelf life); slightly more grain than D-76.
• Ilford Microphen — designed as a speed-increasing developer; 7:30 stock at 68°F for EI 400, or push to EI 800 without extended time. Preferred for push workflows.
• Kodak XTOL 1:1 — fine-grain alternative to D-76; 9:00 at 68°F for EI 400. Cleaner grain; slightly softer shadow detail.
• Agfa Rodinal 1:25 or 1:50 — maximum acutance; 9:00 at 68°F for 1:50. Grain is pronounced; sharpness impressive.

Reciprocity failure

Tri-X follows classic cubic-grain reciprocity behavior. Approximate Schwarzschild exponent: p ≈ 1.3.

Metered exposure	Actual exposure	Correction
1s	~1.5s	+½ stop
10s	~30-50s	+1½ stops
60s	5-10 min	+3 stops

See [[reciprocity-failure]] for the mechanism and Reciprocity Failure Compensation for the full per-stock comparison table.^[1]

Tonal palette

Tri-X's signature: warm-leaning B&W rendering with forgiving tonal compression:

• Shadows — warm undertones; block up gracefully rather than sharply
• Midtones — creamy, gradual transitions; flatters skin
• Highlights — bloom slightly, which reads as "photographic" rather than digital-sharp
• Grain — visible, structured, tactile. Grain character varies with developer choice (Rodinal pronounced; XTOL subdued).

This is the "classic black-and-white film look" — what most people mean when they say B&W photography should look a certain way.

Comparison with competitors

Film	Grain	Tonal character	Push latitude	Reciprocity
Tri-X 400 (this film)	Coarse, structured	Warm, classic	Excellent to EI 1600; usable to 3200	Standard cubic p≈1.3
Ilford HP5 Plus 400	Similar	Ilford-warm	Similar; Microphen preferred	Similar p≈1.3
Kodak T-Max 400	Fine (T-grain)	Cooler, more modern	Excellent; different character	Better (p≈1.1)
Ilford Delta 400	Fine (T-grain)	Neutral Ilford palette	Clean to EI 1600	Better (p≈1.1)
Fuji Neopan 400 (discontinued)	Medium	Crisp neutral	Similar to HP5+	Similar to T-Max 400

Tri-X's distinctive position: the most forgiving, most versatile, most "classic" option. Photographers who want fine grain or modern tonal character look elsewhere (T-Max or Delta); photographers who want The B&W Film Look stay with Tri-X.

Format availability

Tri-X 400 is currently available in:

• 35mm — 36-exposure cassettes, pro packs of 5
• 120 — 5-roll pro packs (no single-roll retail)
• 4×5 — 50-sheet boxes
• 8×10 — 25-sheet boxes

The 4×5 and 8×10 sheet formats are particularly notable — few fast B&W films are available in sheet today (T-Max 400 and HP5 Plus being the main alternatives).

Famous users and cultural impact

• Robert Frank — The Americans (1958); shot extensively on Tri-X at EI 400
• Garry Winogrand — street photography; Tri-X at EI 1600 push was his constant rating
• Diane Arbus — portraits, sometimes pushed, always Tri-X
• Daido Moriyama — the extreme-push aesthetic (EI 3200+); defined Japanese street photography
• Eugene Smith — Pittsburgh project (1955–58); Minamata (1971–75)
• Sebastião Salgado — extensive documentary/landscape work (though also used Tri-X's larger-format sheet equivalents)

Tri-X's cultural weight in photography exceeds any other film stock — it is implicitly "B&W film" in popular imagination.

Workflow recommendations per use case

• Street photography — EI 400 in HC-110 Dil B at 5:45; or EI 1600 in Microphen for the Winogrand push aesthetic
• Portrait — EI 320 (overexpose ¼ stop) in D-76 1:1 at 9:30; smoother skin rendering
• Landscape — EI 250 (overexpose ⅔ stop) in XTOL 1:1 at 9:00; cleaner grain at enlargement sizes
• Available-light documentary — EI 1600 in Microphen; accept grain + contrast as aesthetic
• Sheet film work — EI 400 in HC-110 Dil B or D-76 1:1; Tri-X's sheet formats excel for large-format B&W where grain is effectively invisible

Related films and techniques

• Push Processing — Tri-X's home territory
• Pull Processing — Tri-X pulls gracefully; worked beach-at-noon example uses HP5+ but Tri-X behaves similarly
• Reciprocity Failure Compensation — Tri-X is the baseline comparison in the per-stock table
• Zone System Exposure — Tri-X is the canonical Zone System B&W film
• Ilford Delta 400 — closest T-grain competitor
• Fuji Neopan 400 (discontinued) — discontinued alternative with crisp-neutral palette