Ilford ID-62

Paper DeveloperStock Solution
Ilford (published formula, pre-1970s)Dilution: 1:3 from stock
warm-tonepaperPQlong shelf lifeDektol competitor

Ilford ID-62 is the PQ counterpart to Dektol — the Ilford equivalent of the MQ paper developer that has set the tone standard for silver gelatin printing for nearly a century. Where Dektol uses the Metol + hydroquinone pair, ID-62 substitutes phenidone for metol and re-balances around it. The result is a paper developer that prints slightly warmer than Dektol at comparable development times, avoids the Metol skin-sensitization hazard entirely, and keeps longer in stock form and working dilution.[1]

ID-62 is a direct competitor to Dektol for every standard silver gelatin paper — RC, FB, neutral, warm-tone. The typical working dilution is 1:3 from stock (1 part stock + 3 parts water), developing at 20 °C for 1.5–2 minutes. Longer development extends midtones; shorter cuts contrast slightly.

When to choose ID-62 over Dektol

  • You want to avoid Metol contact. This is the primary reason most ID-62 users picked it — occupational darkroom skin sensitization was an unsolved problem until phenidone arrived in 1953.
  • You want slightly warmer image tone. ID-62 prints a quarter-stop warmer than Dektol on the same paper, which reads as a more "print-like" visual quality on warm-tone or chlorobromide papers.
  • You want longer working-solution life. A PQ developer shows its exhaustion (colour change, activity loss) more slowly than the Metol form. A single tray of 1:3 ID-62 will out-live a comparable tray of Dektol by roughly a third.
  • You want tighter tonal scale. ID-62 produces a very slightly longer tonal range than Dektol, which can matter on graded papers where you are pushing for either extra highlight detail or deeper shadow separation.

Choosing between ID-62 and Bromophen

Bromophen is Ilford's "universal" PQ paper developer sold as a packaged dry powder — same underlying chemistry as ID-62 but with slightly different ingredient proportions tuned for a broader range of papers. ID-62 is the home-mix version; Bromophen is the factory-packaged version. Practical tone differences are subtle; most workers use whichever is easier to obtain.

Phenidone vs Dimezone-S substitution

Dimezone-S substitutes for phenidone in ID-62 at roughly 80% of the phenidone concentration (0.4 g instead of 0.5 g per liter of stock). The developer then runs with slightly longer working-solution life and marginally cleaner oxidation. The cost is higher per liter, and dimezone-s is less widely stocked than phenidone.

Related recipes

  • Dektol (D-72) — the MQ reference that ID-62 is measured against.
  • Microphen — Ilford's PQ film developer using the same phenidone/hydroquinone pair tuned for negative work.
  • Ethol LPD — alternative PQ paper developer with a different activity profile; used where longer tray life is desired.

References

  1. BOOK Anchell, Steve. The Darkroom Cookbook 4th ed. Focal Press, 2016. ISBN 9781138959170.

Mixing Instructions

Start with 750 ml of water at 50 °C (125 °F). Phenidone is sparingly soluble in cold water — working from warm water avoids clumping.

  1. Add sodium sulfite (anhydrous) and stir until fully dissolved. The sulfite goes in first to protect the reducers from premature oxidation.
  2. Add hydroquinone and stir until dissolved.
  3. Dissolve phenidone in a separate small volume of warm water (or 1 g in 20 ml propylene glycol if you keep a phenidone glycol stock), then add to the main bath. Phenidone dissolves poorly in cold water; a warm-water pre-dissolution step prevents clumps.
  4. Add sodium carbonate (monohydrate form) and stir until dissolved — the solution will fizz slightly as it accelerates the pH rise.
  5. Add potassium bromide and stir.
  6. Add benzotriazole (typically pre-dissolved as a 1% stock solution — 20 ml of 1% stock = 0.2 g of benzotriazole) and stir.
  7. Add water to make 1 liter of stock.

Stock life: about 3 months in a tightly capped brown glass bottle, kept cool and dark. Signs of exhaustion: yellow-to-amber colour, developer-ghost smell.

Working dilution: mix 1 part stock + 3 parts water immediately before use. Working-tray life is one full session (roughly 30 sheets of 8x10 in a tray).

Development: 1.5–2 minutes at 20 °C with normal intermittent agitation. Run a test strip for the paper grade and batch before committing a full print.

Ingredients for 1L of Stock Solution

Volume:
ml
#ChemicalRoleQty (1L)UnitNote
1Sodium SulfitePreservative50.0g
2HydroquinoneDeveloping Agent12.0g
3PhenidoneDeveloping Agent0.5g
4Sodium CarbonateAccelerator60.0g(monohydrate form)
5Potassium BromideRestrainer2.0g
6BenzotriazoleRestrainer0.2g