Archival Washing Tests (Part 2: Ilford Rapid Fixer)

This is the second of a four-part series relating the results of my archival print washing tests. The first part of the series explaining details of print washing and the methods I used for these tests is Part 1: The Background.

Background

In this post, I’ll cover the empirical results of my washing tests with fiber-based prints fixed with Ilford Rapid Fixer. I’ll address the developing and fixing process, along with the wash time results using my DIY archival print washer. If you haven’t seen my previous post regarding my washing setup, you might want to read it first.

Discussion

For this test, I used Oriental Seagull VC-FBII Glossy paper cut into strips of 2 inches by 8 inches. In order to identify them I made a template with four holes at the top with four smaller index holes above them. By covering or exposing the larger holes, I marked the test strips with a binary identifier. It may seem unnecessarily geeky, but I didn’t want to mark the test strips with any type of physical marking like ink that might contaminate the wash water, or might, in some other way affect the test results. I’m sure it was concern over nothing, but I wanted to limit any unnecessary variables. Maybe it was a little geeky.

You’ll see from my photos of the test results that I had a little trouble dialing in the correct exposure to make nice black marks without burning through the card stock I used for the template. As long as I was able to find an unexposed area of the test strip for the residual fixer test solution, I was fine (it’s critical to have a nice white background for the solution to be able to see the resulting stains), but it makes for ugly photos of the results. We’ll consider science a priority over aesthetics for this test.

There were two parts of this test: for the first I used no wash aid, and for the second I used Kodak Hypo Clearing Agent.

To check for residual fixer after washing, I used Photographer’s Formulary Residual Hypo Test. This test solution is used by placing a drop of solution on the print after it’s been washed, and leaving that drop in place for exactly two minutes, after which it’s blotted off. If fixer is still present, a yellowish stain will remain on the print; the more concentrated the residual fixer, the darker the stain. The instructions have this table:

It’s important to examine the results immediately after removing the solution, as the spot will continue to grow darker as the paper and solution dry.

I monitored the temperature of the water in the archival washer, but it stayed pretty consistent at 19°C (66°F). A warmer wash water would have aided washing yielding shorter required wash times, but the water available to run to the washer comes from the cold water line. Fortunately in Central Oklahoma, our cold tap water isn’t too cold, especially in May when I conducted this test.

All the water used for the working solutions and the wash was tap water, but it is filtered. I will admit I don’t know how long the filters have been in place, so they may not be filtering much at all. Our mineral content in the water doesn’t seem to be too high, but filtered water would be better. Distilled water would be better yet, but supplying that to the archival washer is obviously not possible.

From an earlier test on the archival washer, I’ve estimated the flow rate through the washer at approximately 0.4 gallons per minute (1.5 liters per minute.)

All of the test strips were pinned with a plastic clothes pin to a divider, with each test strip on a separate divider. I pinned them at the top of the divider by the bottom of the test strip so the area I would be testing with the solution was well inside the washer.

Process and Results

Test 1 – No wash aid

For all the test strips in the first part of the test (with no wash aid), I used this process:

• Expose a test strip to mark an identifier (in binary, because it was easier than trying to use stencils for numerals)
• 2:00 – Develop in Dektol (standard dilution of 1:2)
• 0:10-0:15 – Kodak Indicator Stop Bath
• 1:00 – Ilford Rapid Fixer (recommended dilution of 1:4)
• 2:00 – Tray wash with Kodak Automatic Print Siphon to remove an initial portion of the fixer before moving to the archival washer
• Variable – Archival wash in my DIY archival washer
• Remove the test strip and squeegee the test strip between my fingers to remove most of the surface water
• 2:00 – Test with Photographer’s Formulary Residual Hypo Test
• Blot the test solution and immediately examine and photograph the results

Note: All times are in minutes and seconds (m:ss)

The photos below show the spots after use of the test solution. The pen in some of the photos is pointing to the area tested on the test strips where the resulting spot was difficult or nearly impossible to identify after the solution was removed. That’s a good thing, and exactly what we want to (not) see.

The time spent in the archival washer is shown below each print. If you’re familiar with binary, you’ll note strip 3 is between strip 1 and strip 2. That was an error on my part when I exposed it, and I didn’t notice it until it was already in the washer with the timer running.

There’s very little difference between the stains at 60 and 65 minutes, and they are very faint stains. From this test, I’d say I have an adequately washed print at the 60 minute mark.

Test 2 – With wash aid

For the test strips in the second part of the test using a wash aid, I used this process (differences from the first test are in boldface):

• Expose a test strip to mark an identifier (in binary, because it was easier than trying to use stencils for numerals)
• 2:00 – Develop in Dektol (standard dilution of 1:2)
• 0:10-0:15 – Kodak Indicator Stop Bath
• 1:00 – Ilford Rapid Fixer (recommended dilution of 1:4)
• 5:00 – Tray wash with Kodak Automatic Print Siphon to remove an initial portion of the fixer before moving to the wash aid
• 10:00 – Kodak Hypo Clearing Agent
• Variable – Archival wash in my DIY archival washer
• Remove the test strip and squeegee the test strip between my fingers to remove most of the surface water
• 2:00 – Test with Photographer’s Formulary Residual Hypo Test
• Blot the test solution and immediately examine and photograph the results

Note: All times are in minutes and seconds (m:ss)

Again, you can see the results of this test in the photos below.

The stain at 18 minutes is barely noticeable, and is pretty much gone at the 21 minute mark. If I had known it would clear so quickly, I’d have started testing the strips around 12 minutes to see the gradual improvement in clearing.

Conclusion

The results demonstrate successful washing given adequate time. I think I’d have seen similar results with tray washing, but only if washing one, or maybe two prints at a time. With my DIY archival washer, I’m confident of consistent washing for all the prints.

Using no wash aid, I saw adequate washing in 60 minutes, which is consistent with other results I’ve seen and heard of for fiber-based prints. The anecdotal information regarding wash times with a wash aid usually seems to be half the time of washing without a wash aid. I demonstrated even better performance than that, with a clearing time of 18-21 minutes.

For my personal workflow, I would rather not use the wash aid, opting to wash for a longer time in the archival washer. Prints in the washer require no time or attention. To use a wash aid I have to put every print in the wash aid tray, and agitate it regularly. That was ten minutes per print in the test above, requiring my regular attention and keeping me from doing much else. I could lower the wash aid time and raise the archival washing time, but that still requires my attention for each print in the wash aid, albeit for a few minutes less.

Regarding my workflow, I typically tone all my prints with selenium toner. I’ve experienced staining of highlights during toning when I haven’t washed the prints adequately after fixing. Based on these test results, I will standardize my workflow to do a complete wash of the prints after fixing, with no wash aid in between. After they’re washed, I will either tone at that point, or let them dry and come back later for a toning session. Either way, I’ll have prints I’m sure have been washed thoroughly.

Regarding selenium toning, since the Kodak Rapid Selenium Toner I use contains ammonium thiosulfate which is also a component of many rapid fixers, it is vital to have a thorough wash after toning, especially since this will be the last time the print is washed. My next post will cover the tests I performed on the test strips above to selenium tone, wash, then test again to determine the adequate wash time after toning.