Black-and-white negative · Black & white
Ilford Delta 400
Fine-grain 400 speed for action and fine art.
Ilford Delta 400 printed on Kodak 2302: a 400-speed film with fine grain for its speed. Original vs Ashigrain.
At a glance
- Exposure index
- 400
- Introduced
- by 2002
- In production
- Process
- ILFORD ID-11 (stock)
About the film
Ilford Delta 400 Professional is a fast, fine-grain panchromatic black-and-white negative rated ISO 400/27°. No source read dates its launch, but by September 2002 it was sold as Delta 400 Professional, in a sheet published by Ilford Imaging UK at Town Lane, Mobberley, so the film existed by 2002.
Ilford's own timeline records a first Delta film built on core-shell crystal technology but does not name it, so it does not date Delta 400. Ilford's timeline says a management buy-out in 2005 formed HARMAN technology Limited, which trades as Ilford Photo in Mobberley, Cheshire. HARMAN technology publishes the current sheet, dated November 2018. Ilford recommends the film for action and available light and for fine-grain pictorial and fine-art work, and says it prints well at meter settings up to EI 3200 with extended development. Ilford also says it performs well in seasoned developers. It comes in 135 on acetate base and in 120 on clear acetate with an anti-halation backing that clears in development.
Sources for this history
- ILFORD DELTA 400 PROFESSIONAL fact sheet (September 2002), ILFORD Imaging UK Limited
- ILFORD DELTA 400 PROFESSIONAL technical information (November 2018), HARMAN technology Limited
- ILFORD PHOTO History, HARMAN technology Limited
The look
Ilford Delta 400 Professional is a fast ISO 400 panchromatic black-and-white negative with fine grain, made for action and available light as well as pictorial work. It prints on Kodak B&W Print Film 2302 by default, or on a colour print film for a near-neutral image with the print's own tint.






Best for
- Available-light portraits
- Action and events indoors
- Fine-grain street photography
Compare camera films
Science & sources


A fast panchromatic black-and-white negative rated at ISO 400. Its curve and spectral sensitivity are digitised from Ilford's 2002 sheet, cross-checked against the 2018 edition; the spectral shape is relative, read from a spectrogram made with 2850 K tungsten light. Ilford prints no MTF or granularity, so its sharpness and grain are proxied from Kodak T-Max 400. It prints on Kodak B&W Print Film 2302 by default.
Response curves and the evidence behind the model
Compare manufacturer data with Ashigrain’s response on the same axes. These curves show how the model is calibrated to its sources; they do not establish a match to photographed film.
Characteristic response
RMS granularity
Density variation (σD). Where the datasheet gives a single grain value, the response away from that point is an approximation.
| Channel | Density | Datasheet-based σD | Model σD |
|---|---|---|---|
| N | 0.3 | 0.005479 | 0.005375 |
| N | 0.6 | 0.007749 | 0.007602 |
| N | 1 | 0.010004 | 0.009814 |
| N | 1.5 | 0.012252 | 0.012019 |
Model limits
These images show the film model in use. Spectral response, lighting and viewing conditions include approximations. Halation, bloom, grain size, weave and flicker are not fully measured for each film. The look of real film also depends on development and print timing.
- Custom lighting spectra, camera metering and the spectral reflectance inferred from fixed-white-balance footage are assumptions used by the model, not measurements of this film.
- The source gives a daylight ISO speed but no colour balance. Daylight calibration and spectrally neutral silver density are assumptions.
- The characteristic curve uses a relative log exposure axis with no lux-second scale and no marked normal exposure; its normal-exposure point is assumed.
- The spectral sensitivity is the envelope of a wedge spectrogram made with 2850 K tungsten light, used relative to its own printed scale. The spectrogram-to-sensitivity conversion is not printed, and the 2850 K light is not divided out.
- Neither edition prints an MTF or granularity. Both are proxied from Kodak T-Max 400, the tabular-grain Kodak black-and-white negative of the same speed, so the sharpness and granularity shown are that film's, not measurements of Delta 400.
- No push curves are published; push and pull use a generic model.
- The sheet's reciprocity power law starts at ½ s; the model applies it from 1 s, so exposures between ½ s and 1 s get no correction. The sheet gives no upper limit to the law's validity.
- The anti-halation backing is described only for roll and sheet film, not 135, so halation is off by default. Its strength, radius and bloom are not measured.
- Characteristic response outside the published exposure range is an extrapolation, not measured film data.
- In the print branch it prints on Kodak B&W Print Film 2302 by default. Black-and-white print timing is modelled.
Reciprocity: modelled from 1/10000 s to 100 s, following the datasheet's corrections for long and short exposures. Exposure time stops at the ends of that range.
Film guide: assumptions and practical choices
Sources
- Exposure index: ILFORD DELTA 400 PROFESSIONAL fact sheet, September 2002, p. 1
- Characteristic curves: ILFORD DELTA 400 PROFESSIONAL fact sheet, September 2002, p. 6
- Process: ILFORD DELTA 400 PROFESSIONAL fact sheet, September 2002, p. 6