Processing a film

Purpose

To take one exposed film from a dry reel to a hanging negative under conditions you can write down and repeat, and to know at the end which numbers were the maker’s and which were yours.

When to use it

Every film. The snapshot roll and the fifth strip of a controlled series get the same sequence; what changes is how much of it you record. Paper goes through the archival print sequence instead, which has different times, a different wash and a different failure.

Before you start

You should already be able to thread your reel with your eyes shut, dilute to a stated volume by the stock procedure, and read a maker’s development table, all from Part VI’s processing lab. Where a result has to compare with another result, hold every input still except one, as Part IX requires.

On the bench, laid out left to right and not moved once the light is off: the dry tank, lid and sealing ring; the reel, completely dry; scissors; developer, stop, fixer and wetting agent, each diluted for the tank’s own stated volume; a thermometer; a water bath; a timer; the coupon pot; the wash vessel; the clip and weight; the notebook and the capacity log; the labelled waste containers, silver-bearing among them. Run lab opening first.

Procedure

1. Check the room dark. ILFORD’s test is five minutes in it with the lights out and your eyes adapting; a leak you cannot see after five minutes you will not see at all.
2. Read your development time from the sheet for your film in your developer at your dilution, and write down which table it came from and whether it is a tank figure or a tray one.
3. Copy that sheet’s agitation scheme into the notebook as well. It is an input of the same standing as time and temperature, and the table was drawn up with it.
4. Stand all four solutions in a water bath a couple of degrees warmer than the working temperature and bring them together. The developer sets the figure; the stop, the fixer and the wash water go within 5 °C of it.
5. Practise the load in the light with a spoiled film, then with your eyes shut, then stop.
6. Lights off. Load: on sheet film find the notch and seat the sheet under both rails; on roll film put the lugs towards you, feed about 5 cm into the first channel and rotate the halves.
7. Cut a scrap from the same unexposed stock into the coupon pot before the box closes.
8. Close the tank, fit the lid, and only then put the light on.
9. Confirm the temperatures again at the tank, with the thermometer rather than by hand.
10. Pour the developer in smoothly and start the clock as you finish pouring.
11. Agitate to the scheme from step 3, tapping the tank on the bench after each set.
12. Begin pouring the developer out 15 seconds before the nominal time, so the clock reaches the mark as the tank empties.
13. Pour in the stop at its published dilution, invert twice, and pour it out after ten seconds.
14. Measure today’s clearing time on the coupon by the clearing-time test, then fix for twice that time, agitating as you agitated in development.
15. Return the fixer to its bottle and add this film to its running total in the capacity log.
16. Wash by one published route and say which: running water for 5 to 10 minutes within 5 °C of the process temperature, or the tank sequence of three fills inverted five, ten and twenty times. Where your film’s own sheet gives a different figure, that one governs.
17. Rinse in wetting agent at its published dilution, measured, and lift the film out.
18. Draw a clean squeegee down it once, hang it with a weighted clip in still, dust-free air, clear of the floor, and leave it alone until it is dry.
19. Route the waste. Developer and stop to their own containers by the general waste procedure; the fixer and the first wash to silver-bearing waste. Both end at the disposal caveat, which is the page that says why the route is yours to find out and not this course’s to give.

How you know it worked

• The rebates, or the strip under the holder’s rails, are clear rather than milky.
• The highlights are dense enough that print is only just readable through them, which is the maker’s own by-eye standard for a correctly exposed and processed negative.
• The fixing time you used was twice a clearing time you measured today, not a number you remembered.
• Nothing ran unevenly down the film as it dried.
• The notebook carries the film, the developer and dilution, the time, the temperature, the agitation scheme and the wash route, and each of those is a figure rather than an adjective.

If a step fails

Step 2, no published time for your film in your developer. Do not interpolate silently. Use the nearest published figure, record it as nearest-published rather than published, and treat the first film as the test.

Step 4, you cannot hold the temperature. Hold whatever you can hold steadily and use the maker’s compensation chart to move the time. A steady 24 °C with the time corrected is a usable film; a drift from 22 °C to 17 °C is not. Do not accept a corrected time under five minutes — below that the compensation chart itself stops recommending the result.

Step 6, the film jams half way onto the reel. The reel is damp, and there is no rescue in the dark: put the film back in its can or the tank body, close it, dry the reel completely, and start again.

Step 11, you missed an agitation set. Note the miss and its time. Do not compensate with an extra set: that is two changes instead of one.

Step 14, the clearing time is outside the maker’s published band. A long one says the bath is spent — retire it by the test’s own rule and fix in a fresh one. A short one usually says the coupon was not from the same stock.

Step 14, the film is milky when the tank is opened. It is under-fixed and nothing is lost yet. Put it straight back into fresh fixer for twice the new clearing time and wash it again from the beginning.

Step 16, running water is not available at temperature. Use the three-fill inversion sequence, which is a published specification and not a compromise.

Step 18, the film dries with streaks or drying marks. The wetting agent was absent, too weak or too strong; the maker warns that too much gives uneven drying as surely as too little. Rewash, re-rinse at the measured dilution and rehang.

What to record

One line per film in the log: the date; the film and batch; the developer, its version or product and its dilution; the development time with the table it came from; the temperature of all four baths; the agitation scheme; today’s clearing time and the fixing time taken from it; the wash route; the fixer’s running total after this film; and anything you did that this procedure does not say to do. That last column is the one that changes the procedure next time.