IlfordHP5 Plus

Ilford HP5 Plus is an ISO 400 panchromatic black-and-white negative film, made in England by Harman technology under the Ilford Photo brand. Harman sells it for action, available light and general photography, and rates it for good prints up to EI 3200 with extended development [1]. It has carried the HP5 Plus name since 1989 and is the usual counterpart to Kodak Tri-X [3] [4].

Look and color

HP5 Plus turns colors into grays according to its own spectral sensitivity, not the eye’s:

• More weight on blue. Harman’s spectrogram is measured under tungsten light. Once that light is compensated for, blue weighs more than on Tri-X: in the weights computed from the two datasheets, the Z weight, which carries most of the blue, is 0.49 for HP5 Plus against 0.39 for Tri-X [1] [17]. darktable’s built-in “monochrome | ILFORD HP5+” preset is built from the same datasheet [14].
• Measured on our test RAW files. With those weights instead of plain luminance, a sky came out 4.1 L* lighter, skin 5.7 L* darker and a pink shirt 2.6 L* darker; the same conversion with the Tri-X curve moved them by +3.2, −3.8 and −1.2 [17].
• No review describes how HP5 Plus renders skies, skin or reds, so this section relies on the datasheet.
• Tones. The Darkroom speaks of “beautifully subtle tones, medium to low contrast” [8]. For Emulsive, much of the range is “bunched up in those lovely mid-tones, although highlights and deep blacks are represented very well” [5].

Tonality

• Curve. Harman publishes one characteristic curve, for Ilfotec HC 1+31, 6½ minutes at 20 °C. Base plus fog sits near 0.18; the toe spans about one log unit; the straight section has a slope of about 0.64, with no shoulder up to a density of 2.1 (our reading of the graph) [1]. The Tri-X curves are for other developers, so the two datasheets alone do not say which film is more contrasty.
• Contrast: medium, with dissenters. Ilford calls it “medium contrast” [2], and Emulsive gets “a medium contrast result” at box speed [5]. Next to Tri-X it looks “a little flatter” [10] or “more nuanced and balanced” [11]. The Darkroom credits it with “strong tonality without crushing blacks” [9]. Casual Photophile, on the other hand, writes of its “characteristic high contrast” [7].
• Where the contrast sits. Reading the published curves, 35mmc’s Aukje concluded that “Tri-X will display more contrast in the highlights, where HP5+ will give more contrast in the shadows” [12].
• Shadows: the sources disagree.
  • More detail than Tri-X: “its shadows retain more detail than many comparable films (including Tri-X)” [6]; “the winner again for the details in the shadows” [10].
  • Less: HP5 Plus “retains less shadow detail than other films in its segment” [7]; “some fall-off in shadow detail in especially dark scenes” [5].
• Highlights: “least likely to get washed out by over-exposure” [6].
• Latitude. Harman gives good results from EI 400 to 3200 and notes that this range comes from practical evaluation, not the ISO method [1]. Reviews praise its latitude [5] [8] [11]; from the curve, Analog.cafe estimates about 12 stops [6]. The Darkroom notes that it is “easily pushed to 800 or 1600 for added contrast” [8].
• Long exposures: no correction from 1/10,000 to ½ s; beyond, Harman’s formula gives adjusted time = metered time^1.31 [1].

Grain and sharpness

• Harman publishes no granularity, resolving power or MTF figure for HP5 Plus [1], as reviewers have noted [12].
• Reviews disagree on HP5 Plus against Tri-X:
  • Less grainy: Tri-X is “much grittier/grainer” (sic) [5]; HP5 Plus has “a more subdued grain profile” [11].
  • Grainier: “slightly grittier than Kodak Tri-X 400”, by the author’s eye [6]; “a tad larger grain”, as many describe it [13].
• Casual Photophile finds the grain “certainly present” but not in the way of sharpness [7].

Spectral sensitivity

Under 2850 K tungsten light, sensitivity rises from about 352 nm to a broad plateau between 445 and 480 nm, dips slightly around 500 nm, peaks around 570 to 580 nm, shows a small bump near 625 nm, then falls steeply from 630 nm to the baseline near 658 nm [1]. Corrected for that light, the curve gives more weight to blue than Tri-X: skies turn lighter, skin and reds darker than in a luminance conversion [17].

Names, status and history

• 1931 to 1989. HP began as Hypersensitive Panchromatic plates in 1931 and was sold as HP film from 1935 [4]. HP5 was launched in 1976, and HP5 Plus introduced in 1989 [3].
• Harman. Since a 2005 management buyout, the film is made by Harman technology, which trades as Ilford Photo at Mobberley, Cheshire [3].
• Formats. The datasheet lists 35 mm in 24 and 36 exposures and 30.5 m (100 ft) bulk, 120 roll film and sheet film, and DX-coded cassettes [1]. On September 29, 2026, Ilford listed 35 mm, bulk, 120 and sheet film [2].
• Push. Ilford’s product page says it “can be rated up to El 3200/36°” (sic) [2].
• Datasheet. The current edition dates from November 2018 [1].