Development time
Kodak Tri-X 320 (320TXP) in HC-110
4:15 at 20°C (68°F), 1+31 dilution, box speed.
Start timer · 4:15- Time
- 4:15
- Dilution
- 1+31
- Temperature
- 20°C
- Box speed
- ISO 320
All 6 times
| Dilution | EI | Time | Temp | Agitation | Evidence | Timer |
|---|---|---|---|---|---|---|
| 1+31 | 320 | 4:15Sources differ | 20°C / 68°F | Standard | ManufacturerChecked Oct 2026 | Start timer |
| 1+31 | 320 | 4:00Sources differ | 21°C / 70°F | Standard | ManufacturerChecked Oct 2026 | Start timer |
| 1+31 | 320 | 3:00Sources differ | 24°C / 75°F | Standard | ManufacturerChecked Oct 2026 | Start timer |
| 1+31 | 320 | 4:45Sources differ | 20°C / 68°F | Standard | ManufacturerChecked Oct 2026 | Start timer |
| 1+31 | 320 | 4:15Sources differ | 21°C / 70°F | Standard | ManufacturerChecked Oct 2026 | Start timer |
| 1+31 | 320 | 3:30Sources differ | 24°C / 75°F | Standard | ManufacturerChecked Oct 2026 | Start timer |
EI is the speed the film was rated at when shooting. Evidence says where each time comes from: the manufacturer’s own data, a named test, a compilation or several agreeing reports (community consensus), or one person’s report. Times marked “not yet verified” come from secondary sources and haven’t been checked against a manufacturer datasheet. Where sources give different times, every one is listed and marked “sources differ”.
Other temperatures
| 18°C64°F | 19°C66°F | 20°C68°F | 21°C70°F | 22°C72°F | 23°C73°F | 24°C75°F |
|---|---|---|---|---|---|---|
| 5:19 | 4:46 | 4:15 | 3:50 | 3:24 | 3:04 | 2:46 |
Calculated from the 20°C (68°F) time using Ilford’s temperature compensation factors, not taken from a datasheet. Most B&W developers behave well between 18–24°C (64–75°F).
Mixing
| Dilution | 300 ml (10.1 fl oz) (one 35mm roll) | 500 ml (16.9 fl oz) (one 120 roll) |
|---|---|---|
| 1+31 | 9.4 ml developer + 291 ml water | 16 ml developer + 484 ml water |
How they work together
- HC-110
- Fine grain, high acutance, full film speed, normal contrast. Full-scale with good shadow detail.
- Kodak Tri-X 320 (320TXP)
- Sheet-film sibling of Tri-X 400 on a thick ESTAR base, designed for controlled studio and low-flare lighting; roll-film versions ended in 2010 and only sheet sizes remain.
- Notes on this pairing
- Sheet film, large tank, agitation at 1-minute intervals (F-4017 gives no small-tank time for sheets). Kodak dilution B. Kodak warns tank times under 5 min may give uneven development.
- Kodak dilution B. Small tank, agitation every 30 s; J-24 roll-film data for 320TXP. F-4017 large-tank sheet time is 4:15 at 20 °C. Kodak warns tank times under 5 min may give uneven development.
Tri-X 320 (320TXP) in other developers
Other films in HC-110
Kodak Tri-X 400
3:45
1+31 · EI 400 · 20°C · 6 variants
Kodak T-Max 400
5:30
1+31 · EI 400 · 20°C · 7 variants
Ilford HP5 Plus
5:00
1+31 · EI 400 · 20°C · 7 variants
Ilford Delta 400
7:30
1+31 · EI 400 · 20°C · 8 variants
Ilford FP4 Plus
4:30
1+15 · EI 125 · 20°C · 5 variants
Foma Bohemia Fomapan 400 Action
6:30
1+31 · EI 400 · 20°C · 2 variants
Harman Technology Kentmere Pan 400
8:00
1+31 · EI 400 · 20°C
Ilford Ilford Delta 100
6:00
1+31 · EI 100 · 20°C · 3 variants