Studying at the CCP we recently selenium toned a negative to intensify (increase density range). We ere provided with a negative copy of an Ansel Adams photograph of Mt Williamson. See the original below.
So I developed a control copy the same scene, from a from a negative copy of the original. Reasonable to say that I under developed the print, so I am no Ansel. Shown below is a scanned copy of a developed Ilford Matt fiber multigrade paper.
Anyway, my print developing skills, or lack of them, were not the point here. The point was to have a controlled experiment on the effect of selenium toning the negative, and then developing a print with the exactly the same process.
Under the identical print development conditions, the selenium toned negative produced the following outcome.
Now it is entirely reasonable that a better development of the first negative would have produced a better print, but the thing I found quite startling was the level of improvement. The details in the shadows and the highlights improved superbly.
The negative was selenium toned for 1 minuted and washed. The technique used was a bit like a teabag dipping and gives some agitation to the process. I would not suggest that you just immediately hop into a 1 minute intensification process. You may find it goes to far and the time really will be related to how much intensification is acceptable. So perhaps start with something a bit smaller, say 30 seconds, and check the results before you go any further.
So, if you have any negatives out there that look a little flat and are a fabulous subject matter, have a think about selenium toning. PLEASE BE AWARE… it is NOT reversible.