Re: uncurve/curve comparison on Loris' website
P.S. Perhaps a further explanation of what I mean by "absolute" vs relative tonal values may be useful:
Since there's no relationship between negative density and gum print tones in an absolute sense, only in a relative sense within a specific print layer, the term "shadows," for example, has come to mean weird things. When we use "shadows" to mean the darkest tones of a print even if the next to darkest "shadow" is actually in the midtone range, like a reflection density of say .60 or .75, then what are we talking about? Black and white printers have zones as a convention to talk about print values; everyone knows what a zone III or zone VIII looks like. (Someone on APUG who prints lovely high-key palladium prints recently said proudly that his prints run all the way from Zone VIII to Zone IX, or something like that).
We need a similar convention for gum printers, reflection densities or something, so we can talk about print tonalities in a common language. I've been puzzled sometimes, for example, when people have posted gum prints with a DMax that appears to be well under 1.00 (in other words falling in an area I would call midtones rather than shadows) and commented about how impressed they are that their curve gives them "open shadows," when IME, the pigment mix they've chosen couldn't possibly give them anything but open tones, regardless of the curve, since it's the nature of lighter pigment mixes that they tend to print all the tones in any negative that you give them, and to my eye there are simply no shadows in any meaningful sense in the print. Now if someone used a pigment mix with a potential DMax of 1.8, and found a curve that allowed the mix to express its DMax and still give open shadows as well as separation in the midtones and highlights, then I would be truly impressed. I wonder if perhaps we could settle on a convention that "shadows" has to refer to reflection densities above say .95, and "highlights" has to refer to reflection densities below say .25.
As for whether prints should include all tones from black to white, that's something I don't even agree with for silver prints, let alone gum prints. I personally tend to photograph scenes that don't include really dark tones (the lack of sunlight in my part of the world tends to scenes of low contrast, which I like anyway because low contrast is more peaceful than strong contrast, and I like peaceful images) and there was a period of time when I deliberately printed all my prints very high key because that's the way I wanted to print for a while. There were several reasons for that, but mainly I just happened to be fascinated at that time with seeing how subtly I could print the tones in a narrow range of highlights and light midtones, using only pigment concentration as a control variable. The skunk cabbage print that I linked in the "two tricolor prints" thread this morning (I'm sorry these two threads have got crossed) is an example of a tricolor gum print that I made during that period.
It should go without saying by now that I don't think there's any one best way of printing gum. Low-key prints, middle-value prints, high- key prints, prints of full tonal range, are all potentially beautiful and interesting. My gum printing over time has included a fair share of all these types. So I'm not advocating for a particular tonal range, but I do think it would be good if we had a common language for talking about value ranges.