For those interested, these two sets of tests were made on Ilford Warmtone Fiber: the first on my standard, semi-matte; the second on gloss surface, which I normally use only for proofing. The developer was EcoPro. Toning was carried out at approximately 68 degrees F. Prints were thoroughly washed before toning.

I made whole-sheet graduated “step tablets” in the manner of making test strips, having worked out the times needed to produce Zones I through IX on different grades, 1, 2, and 3. These I cut into strips for toning. Images and step-tablets are not the same, of course; I made these only as general guides.

I normally start with a 1:19 dilution. At 1:29, I found that toning was minimal and slow to change. I took it up to 20 minutes, which very closely matched 7 minutes at 1:19—no benefit. The hope that it might tone high and low values more closely was not realized.

At 1:19, a slight density gain and a slight color shift in the lowest values seems to occur within a two minutes. Five minutes offered noticeable density gain in the lowest values and only a subtle color shift toward purplish brown. At 7 minutes, the density further increased, and the color continued to warm noticeably up through Zone V, less above that, with a subtle appearance of split toning as a result. At 9 minutes, the color was noticeably richer at the bottom end and only somewhat so at V and above. At 12 minutes, the split was enhanced beyond my preference. For 1:19, the area between 5 and 7 minutes is probably where most of my prints will land.

Having found the split-toning effect to generally become equally pronounced at somewhat lower dilutions, I tested at 2:9 (approximately 1:5), which had yielded more chocolatey tones, with more consistent toning over the tonal range, in a test some years ago. These tests confirmed that. However, times are much shorter! At three minutes, a very slightly-reddish/brown print is obtained, with the high values warming along with the lows. At one minute and one-and-a-half minutes, prints similar to 7- to 9-minute 1:19 prints may be created, but the lower dilution offers just a hint more toning (color change) in the higher values than the 1:19. At 2 and 2-and-a-half minutes, the result is quite warm, with the tonal change reaching up into the high values more than the shorter times. Small changes in time have significant effects, but the shortness of time may also be problematic for some artists and could produce uneven toning in a large print.

Finally, it seems to me that the color of the gloss paper for a given time equal to that for the semi-matte, especially in the 2:9 dilution, gave a somewhat less purple and more brown tone. However, other variables may be at work here, and I may retest to confirm or override this.

For me, in any case, these two dilutions offer a fairly full range of options for the kinds of print I envision on this paper.