A few weeks ago there was a discussion about whether to use an acid stop with film or plain water. During that discussion the topic of washing methods came up and I said I would test the published washing methods of both Kodak and Ilford by following them to the letter and then use the standard Residual Hypo test and compare the results to the Hypo Estimator card. After finally getting through the university red tape I have received my silver nitrate to mix the test solution and have conducted the tests. In order to be thorough, I retested everything to verify my results.

All film used was Kodak T-Max 400 TMY-II in 120 format and all rolls were processed using the exact same steps and temperatures with the exceptions noted in the fixing and washing cycles. The images are titled according to whether a hardening or non-hardening fixer was used (Kodak Rapid Fixer with or without part B), if Kodak HCA was used, and the washing method used.

I used running water for some tests, and used the specified flow rate as determined by a flowmeter and the test for efficient flowrate explained in Conservation of Photographs Kodak Publication F-40, 1985.

The washing methods published are:
Kodak's:
A 5 minute running water wash at a rate that changes the water once in 5 minutes when using a hardening fixer and HCA or 10 Fill and Dumps. If a hardening fixer is used without HCA, then a 20-30 minute running water wash (at the same rate) should be used. I include the results from only 10 minutes to be thorough.

Ilford's:
Fill the tank with water and agitate for 5 inversions, then empty. Fill and agitate 10 inversions, then empty. Fill and agitate 20 inversions, then empty. This assumes a nonhardening fixer and no HCA.

The washing methods tested were as follows:

Kodak- 5 minutes of running water, with hardening fixer and HCA
Kodak- 5 minutes of running water, with nonhardening fixer and HCA

Kodak- 10 minutes of running water, with hardening fixer without HCA
Kodak- 20 minutes of running water, with hardening fixer without HCA
Kodak- 30 minutes of running water, with hardening fixer without HCA

Kodak- 10 minutes of running water, with nonhardening fixer without HCA
Kodak- 20 minutes of running water, with nonhardening fixer without HCA
Kodak- 30 minutes of running water, with nonhardening fixer without HCA

Kodak- 10 Fill and Dump, with hardening fixer and HCA
Kodak- 10 Fill and Dump, with hardening fixer without HCA
Kodak- 10 Fill and Dump, with nonhardening fixer and HCA
Kodak- 10 Fill and Dump, with nonhardening fixer without HCA

Ilford- 3 Fill and Dump with Agitation, with nonhardening fixer without HCA
Ilford- 3 Fill and Dump with Agitation, with hardening fixer and HCA

I added a couple of variations that aren't published, such as Ilford's method with hardening fixer and HCA, but I figure some people may do this.

The film is compared to a Hypo Estimator card. The darker the test solution, the more residual hypo in the emulsion. A well washed negative should have little or no staining matching the patch labelled 1 or less.

I offer no conclusions here, I am only presenting results. You can argue which method is best all you want, but the results here are what they are.