You're most welcome, and thanks.
I think I mentioned I was once able to inspect prints of Demachy in the original, and though this is several years back, I vividly remember their subtle tonality. On the back of one print, I recall, a curator had noted that Demachy here was still learning, as there were some blown-out highlights and empty shadows.
I really don't want to endulge in ancestor-worship, but I think it would be very worthwhile to trace the negativs and compare them with the prints in order to learn more about Demachy's printing methods. I also cannot help thinking that his paper, for instance, must have been quite different from today's quality, and I recall him writing somewhere that gelatine sizing is detrimental to gum - a remark I find mystifying.
I think Katharine is right in her suggestion that he used lamp black for his black pictures, probably mixed with some other pigments to vary tonality.
I attach an effort of mine of a single-run gum print in, if I am not very mistaken, bone-black hwich I just scanned in. I hope densities may be more or less recognized.
re paper and other materials 100yrs ago
you have raised what i believe are most important points
my own readings of 1850's era english language photo publications have convinced me that very thoro reading, and examination of original prints, are essential
fox-talbot's waxed paper neg method was derailed when latest batch of paper from his paper suppier, i think 'turkey mill paper manufactury'?, would not work-the supplyer claimed no change in process but talbot could no longer use the paper that was the only support that he had been successful with
i think that all the noise around legal issues drowned out what my readings have convinced me was the real reason for the failure of his method, the paper---probably the size---had changed in a way so that it became unsuitable for the methods talbot had developed
the manufacture of gelatine in the 1800's was a very varied industry-some used fresh hoofs and hides, some used dried, some added this by the handful, some added that in measured amounts, and so on and so on
that an individual using a particular gelatine or a particular paper sized with gelatine could report that HIS experience was that gelatine was nogood under gum--which gum made which way by who for what purpose before he got it?--does not surprise me even tho my own experience is that, in most cases, gum loves gelatine
"gum arabic" was more important than any other substance to the brits when they controled modern day senegal-it was the most neccessary ingrediant in the textile printing industry-
the caravans to the "interior" were sent for the pupose of obtaining the highest grade of raw gum-the slaves that were also brought back with the gum were of much less importance to the brit traders/colonialists/conquerors-they were of less value and the gum took preference in the loading of the ships
i have read the accounts written in english by the captured slaves that came to the states thru this route and also the translations from the arabic into english of those who only wrote in that language, along with the accounts of the brit traders so i am comfident of my knowledge of the brit sourcing and use of gum arabic in the 1700's
concerning the paper-
1800's brit writings talk about 'german'papers and 'french papers' both as prepared albumin paper and/or paper intended for other use-watercolor of course-and writing etc
they were each completely different from each other but consistent in country of origen-- and the use of any went in and out of fashion
re the pigment issues when added to gum--
what is the binder and what are the fillers that each manufacturer uses? gum arabic is listed many times by those who will tell you what the ingredants of the tube or cake are
casien is also used
i myself find that if i mix a pigment that has gumarabic as the binder with gum arabic emulsion my results are more predictable and consistant
i use casien binder pigments with casien for the same reason
i use acrylic binder pigments with synthetic 'gum' emulsions
if you read the photo publications of the times concerning not only the specific process you are using but also other processes, you can become aware of many pertanent facts that will be of great use and application
vaya con dios
Demachy and PBk11
Hi gum printers,
While I was doing something else in the darkroom yesterday, I tried out Demachy's instruction to use as much dichromate as was required in each case to make a mix that was liquid enough to brush out to a thin layer; in other words to use extra dichromate in the case of a heavily pigmented, stiff mix, in order to make it easily brushable.
Since I was doing this between other things, I wasn't paying as much attention as I might, and thoughtlessly exposed the increased dichromate mix (2:1, dichromate:gum/pigment) for the same amount of time (3 minutes) as I had been exposing the same pigment/gum mix used 1:1 with dichromate (27% ammonium dichromate). It was so overexposed that after an hour in the water, even the lightest highlights hadn't begun to emerge; the print was just a black rectangle at that point. I blasted the print with water from a high-pressure faucet, first cool water, then hot water, and also flooded the gum with ammonia, in order to soften it and allow the image to emerge. But as I was doing this, I was thinking that this probably wasn't really so different from Demachy's method. His exposures would have ensured a rather hard layer (10 minutes in direct summer sun) even using 10% potassium dichromate, and then he often employed a forced development, with brushes or with running water.
Anyhow, by using twice as much dichromate as usual, by grossly overexposing, and by forcing development, I was able to force a range of tones from a pigment mix that by my usual method would make a very high-contrast print. But the quality of the tones is very gritty and the tones aren't like continuous tone; it's not a path I would choose as a rule for one-coat gums. But someone who liked the gritty quality might want to exploit this.
The "hot spots" near the nose and on the forehead are where I held the print under the blast of water too long and blasted the gum clean off the paper.
I want to say more about Demachy, but will do that in a separate post.
Lukas, you have the advantage of me in having seen Demachy's prints in person; I can only go by the reproductions I have at hand (in my bookcase and on the web), by remarks of curators and of critics both at the time and more recently, and by the publication "Photo-Aquatint, or the Gum-Bichromate Process" a detailed explanation of the process and description of his methods, written with Alfred Maskell, for the impressions I draw of his work.
Originally Posted by Lukas Werth
Commentators, both past and present, are unanimous in their judgment that he often engaged in heavy retouching of the negative (by painting out areas that he deemed distracting and emphasizing other areas) as well as heavy post-exposure manipulation, and his own writing certainly confirms that impression. He held the idea that a straight photographic print was just a mechanical reproduction of reality, therefore not "art" and in order to make a photograph a work of art, one needed to employ considerable handwork. "Meddling with a gum print may or not add the vital spark; without the meddling, there can be no spark," he wrote. Crawford's summary of Demachy's work: "Demachy was most interested in the painterly and gestural qualities the [gum] process made possible. His prints often made a considerable show of brush strokes, and the tonal scale, instead of having a continuous progression of tones, often jumps in patches from light to dark." Several commentators' descriptions mention his adding white pastel to bring out highlghts in the print.
As I mentioned the other day, I have seen reproductions of some prints that have a subtlety of tone, such as the one of the back of the girl's head done in Venetian red that everyone knows (also a couple of nudes with very delicate tonality) but these don't seem remarkable to me as one-coat gums. Nice, but hardly beyond the reach of any competent modern worker who understands that subtlety of tonality is largely a function of pigmentation.
But as far as the progression of his work over time, the curator's note Lukas mentioned on the back of the print makes no sense to me in the context of the reproductions I've seen. That print in red, showing the woman to have a full head of hair and giving a very nice gradation in the filmy cloud of gauze around her shoulders, is given a date of 1898 in Camera Notes; another print of apparently the same subject with the same hairdo but a different pose, that has the highlights so blown out that it looks like she has a big bald patch on the side of her head, is given the date of 1900. (And it looks that way in a variety of different reproductions, so it's not just one particular reproduction that didn't reflect the print accurately). So I'm not sure that his work could be seen as a progression in the direction of printing a full photographic tonal scale. And while some of the published heavily-pigmented and gritty works (essentially one dark tone, with lighter tones obviously carved out of the darkness with forced development) were dated before 1898, many of the darkest ones with the least tonal gradation were dated between 1902 and 1906 (that's the latest date of any of the reproductions I've seen).
Contemporary photographers who were determined to make artistic photographs by using only the controls and methods inherent to photography rather than borrowing the methods and aesthetics of painting (notably P.H. Emerson) were openly contemptuous of Demachy's work. In answer to one criticism that his prints resembled painting more than photography, he answered that it wasn't like painting at all; while painters use the brush to apply pigment to the surface, he merely uses the brush to remove pigment to reveal the image the camera recorded. Which seems rather an artificial distinction to me, but ... whatever. The point is that from his own remarks and the remarks of observers, as well as from my own observations of (admittedly reproductions of) his work, I'm not led to a conclusion that Demachy's overall goal was to produce in gum a print that reproduced the continuous full-scale tonality of a traditional photograph, although he did do that occasionally, within gum's short-scale limitations.
About the gelatin sizing, I'm perplexed; I didn't know he had ever said that. From the Maskell-Demachy instructions for the gum process: "Some papers may require sizing, though, as a rule, one may be reasonably content with those which ...already possess the desired surface. Should it be necessary to do so, it is easy to size with either gelatine or arrowroot."
I don't "suppose" that he used lamp black for his black prints; I took that directly from the "pigments or colours" section of the "Materials used in the process" section of that same paper. He does mention that it is also possible to use India ink, but adds that it requires very careful grinding and mixing, and concludes that "lampblack, added to ochers and umbers and indigo, will form, separately or combined, a palette with which ...we may be very well satisfied."
Last edited by Katharine Thayer; 07-17-2007 at 07:56 PM. Click to view previous post history.
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Date correction re Demachy
I've become aware that the dates on prints in the books that reproduce images from Camera Notes and Camera Works reflect the date the print was published, not the date that the print was made. The print in red of the back of the woman's head, published in 1898 in Camera Notes as "Study in Red," was apparently printed in 1895; the other print I mentioned earlier being probably the same model but a different pose, also printed in red, with the highlights blown out, I believe is correctly dated at 1900. But I came across a reproduction of a different print of that same image, printed in black and dated 1896, that is a much better print, at least insofar as one can judge from comparing the reproductions, and insofar as we take the definition of being a good print as "somewhat resembling a continuous tone photograph." The impression I took from my reading, as I suggested earlier, is that Demachy wasn't terribly concerned with making prints that looked like photographs; he was more interested in making prints that looked like paintings.
Originally Posted by Katharine Thayer