Ilford Wash Method Card

SIDE A: FILM WASHING

The Principle

Washing is diffusion-limited, not flow-limited. Sequential water changes with agitation are more efficient than continuous running water.

Standard Film Wash (Spiral Tank)

Step Action Time
1 Fill tank with fresh water —
Invert 5 times ~30 sec
Drain completely —
2 Fill tank with fresh water —
Invert 10 times ~45 sec
Drain completely —
3 Fill tank with fresh water —
Invert 20 times ~60 sec
Drain completely —
4 Final rinse with wetting agent 30 sec
Hang to dry —

Total water: ~1.5–2 litres Total time: ~4 minutes

Rotary Drum Wash

Same principle, adapted for rotation:

Step Action Time
1 Fill drum, rotate 1 min
Drain completely —
2 Fill drum, rotate 1 min
Drain completely —
3 Fill drum, rotate 1 min
Drain completely —
4 Wetting agent rinse 30 sec

Total water: ~1.5–2 litres

Why 5-10-20?

Each cycle removes a percentage of remaining fixer. The geometric progression compensates:

  • Cycle 1: Removes ~50% of fixer (5 inversions sufficient)
  • Cycle 2: Removes ~50% of remainder (need more agitation)
  • Cycle 3: Removes ~50% of remainder (need even more)

After 3 cycles: ~87.5% removed → archival standard

Temperature

  • Optimal: 18–24°C (same as processing)
  • Too cold (<15°C): Diffusion slows significantly
  • Too warm (>25°C): Risk of reticulation

Match wash water to processing temperature.

Notes

  • Drain completely between fills—don't just overflow
  • Agitation matters: move the water past the film
  • Wetting agent prevents drying marks (use sparingly)
  • This method meets archival standards per ISO 18917

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SIDE B: PRINT WASHING

RC Paper (Resin Coated)

RC paper doesn't absorb fixer into the base. Washing is quick.

Method Procedure Time Water
Running water Gentle flow over prints 2 min ~4–8 L
Tray changes 3 changes, agitate each 3 min ~3 L

Do not overwash RC paper. Extended washing (>5 min) can cause edge penetration and curl.

Fibre Paper (FB) — Without Wash Aid

Traditional continuous flow method:

Step Action Time
Running water Continuous flow, prints separated 30–60 min

Water use: 40–60+ litres per session

This works but is inefficient. Use HCA method below instead.

Fibre Paper (FB) — With HCA (Recommended)

Hypo Clearing Agent accelerates fixer removal by ion exchange.

Step Action Time
1 Rinse in running water or 2 tray changes 2–5 min
2 HCA bath with intermittent agitation 10 min
3 Final wash: 3 tray fills, agitate each 2 min 6 min

Total time: ~20 minutes Total water: ~10–15 litres (vs. 50+ without HCA)

Sequential Tray Method (Maximum Efficiency)

For fibre paper, after HCA:

Step Fill tray Agitate Drain
1 Fresh water 2 min Completely
2 Fresh water 2 min Completely
3 Fresh water 2 min Completely

Water use: ~6–10 litres for 5 prints

HCA Formula (DIY)

Commercial HCA works well, but you can make your own:

Sodium sulfite     20–30g
Table salt         2–3 teaspoons (optional, accelerates)
Water              1 litre

Cost: ~€0.10/litre vs. ~€0.50 commercial Shelf life: 6 months sealed (discard when yellow)

Archival Washer

If using a slot washer or cascade washer:

Step Action Time
1 Rinse 2–5 min
2 HCA bath 10 min
3 Archival washer 20–30 min

Water use: ~20–25 litres for 6–12 prints (~2–4 L/print)

Advantage: hands-off operation after loading.

Testing Your Wash

Residual hypo test (silver nitrate or commercial test solution):

  1. Apply drop to print margin (unexposed border)
  2. Wait 2 minutes
  3. Blot dry
Result Meaning
No stain Archival ✓
Faint cream Acceptable for display
Yellow/brown Wash longer

Quick Reference

Paper Type Method Water Use Time
RC Running water 4–8 L 2 min
RC Tray changes (3×) 3 L 3 min
FB (no HCA) Running water 50+ L 30–60 min
FB + HCA Sequential trays 10–15 L 20 min
FB + HCA + washer Archival washer 20–25 L 35 min

Savings with HCA: 70–80% reduction in water and time

Sustainable Darkroom series