All my own photography at first was in black and white – I could not have developed and printed my own films, otherwise – but I had no sense that these were ‘lacking’ color. My first camera was a pinhole camera, which gave surprisingly good pictures, with an enormous depth of focus. Then I had a simple fixed-lens box camera – it cost two shillings at Woolworth’s. Then a folding Kodak camera, which took 620 roll film. I was fascinated by the speeds and finenesses of different emulsions, from the slow, fine-grained ones which allowed exquisite detail to the fastest ones, almost fifty times faster than some of the slow emulsions, so that one could take photographs even at night (though these were so grainy one could scarcely enlarge them at all). I looked at some of these different emulsions under the microscope, seeing what the grains of silver actually looked like, and wondered whether one could have grains of silver so small as to produce a virtually grainless emulsion.
I enjoyed making light-sensitive emulsions myself, absurdly crude and slow as they were compared to the ready-made ones. I would take a 10-percent solution of silver nitrate and add it slowly, with continual stirring, to a solution of potassium chloride and gelatin. The crystals suspended in the gelatin were extremely fine and not too light-sensitive, so one could do this safely under a red light. One could make the crystals larger and more sensitive by warming the emulsion for several hours, which would allow the smallest crystals to redissolve and redeposit on the larger ones. After this ‘ripening’, one added a little more gelatin, let it all set to a stiff jelly, and then smeared it on paper.
I could also impregnate paper directly with silver chloride, avoiding the gelatin altogether, by first immersing the paper in a salt solution and then in silver nitrate; the silver chloride formed would be held by the fibers of the paper. Either way, I was able to make my own print-out paper, as it was called, and with this to make contact prints from negatives, or silhouettes of lace or ferns, though it took several minutes of exposure to direct sunlight to obtain these.
Fixing the prints with hypo straight after exposure tended to produce rather ugly brown colors, and this drew me into experimenting with toning of various sorts. The simplest was sepia toning – not (alas) done with cuttlefish ink, sepia, as I had hoped, but by converting the silver of the image to sepia-colored silver sulphide. One could do gold toning, too – this involved immersion in a solution of gold chloride, and produced a bluish purple image, metallic gold being precipitated onto the particles of silver. And if one tried this after sulphide toning, one could get a lovely red color, an image of gold sulphide.
I soon spread from this to other forms of toning. Selenium toning gave a rich reddish color, and palladium- and platinum-toned prints had a fine, sober quality, more delicate, it seemed to me, than the usual silver prints. One had to start with a silver image, of course, because only silver salts were sensitive to light, but then one could replace it with almost any other metal. One could easily replace the silver with copper, uranium, or vanadium. A particularly wild combination was to combine a vanadium salt with an iron salt such as ferric oxalate, and then the yellow of the vanadium ferrocyanide and the blue of the ferri-ferrocyanide would combine to form a brilliant green. I enjoyed disconcerting my parents with pictures of green sunsets, green faces, and fire engines or double-decker buses turned green. My photographic manual also described toning with tin, cobalt, nickel, lead, cadmium, tellurium, and molybdenum – but I had to stop myself at this point, for I was becoming obsessed, going overboard with toning, with the possibility of pressing all the metals I knew into use in the darkroom, and forgetting what photography was really for. This sort of too-muchness had no doubt been noticed at school, for it was around this time that I received a school report that said, ‘Sacks will go far, if he does not go too far.’
There was an oddly massive, chunky camera in Walter’s collection – this, he said, was a color camera: it had two half-silvered mirrors in it, dividing the incoming light into three beams, and these were directed through differently colored filters to three separate plates. Walter’s color camera was a direct descendant of a famous experiment done at the Royal Institution by Clerk Maxwell in 1861, photographing a colored bow with ordinary black-and-white plates through filters of the three primary colors – red, green, and violet – and projecting the black-and-white positives of these images using three lanterns with corresponding filters. When they were all perfectly superimposed, the three black-and-white pictures exploded into full color. With this, Maxwell showed that every color visible to the human eye could be constructed from just these three ‘primary’ colors, because the eye itself had three equivalently ‘tuned’ color receptors, rather than an infinity of color receptors for every conceivable hue and wavelength.
While Walter once demonstrated this to me with three lanterns, I was eager to have this miracle, this sudden explosion of color, more immediately to hand. The most exciting way of getting instant color was by a process called Finlaycolor, in which, in effect, three color-separation negatives were taken simultaneously by using a grid ruled with microscopic red, green, and violet lines. One then made a positive, a lantern slide, from this negative, and brought it into exact alignment with the grid. This was tricky, delicate, but when one had them in perfect register, the previously black-and-white slide would burst into full color. Since the screen, with its microscopic lines, simply appeared grey, one saw, when it was juxtaposed with the slide, the most magical, unexpected creation of color, where seemingly there had been none before. (The National Geographic originally used Finlaycolor, and one could see the fine lines on these if one looked with a magnifying glass.)
To make color prints, one had to print three positive images in the complementary colors – cyan, magenta, and yellow – and then superimpose them. Though there was a film, Kodachrome, that did this automatically, I preferred to do it in the old, delectable way, making separate cyan, magenta, and yellow diapositives from my separation negatives and then floating them gently, one above the other, until I had them in exact superposition. With this, suddenly, marvelously, the colors of the original burst out, having been coded, as it were, in the three monochromes.
I fiddled with these color separations endlessly, seeing the effect of juxtaposing two rather than three colors, or viewing the slides through the wrong filters. These experiments were at once amusing and instructive; they allowed me to create a range of strange color distortions, but above all they taught me to admire the elegance and economy with which the eye and brain worked, and which one could simulate remarkably well with a photographic three-color process.
We also had at the house hundreds of stereoscopic ‘views’ – many on cardboard rectangles, others on glass plates – paired, faded sepia photos of Alpine scenery, the Eiffel Tower, Munich in the 1870s (my mother’s mother was born in Gunzenhausen, a little village some miles from Munich), Victorian beach and street scenes, and industrial scenes of various sorts (one particularly arresting view was of a Victorian factory, with long treadles driven by steam engines, and it was this image that came to my mind when I read about Coketown in Hard Times). I loved feeding these double photographs into the big stereoscope in the drawing room – a massive wooden instrument that stood on its own stand and had brass knobs for focusing and altering the separation of the lenses. Such stereoscopes were still quite common, though no longer as universal as they had been at the turn of the century. Seeing the flat, dim photographs suddenly acquire a new dimension, a real and intensely visible depth, gave them a special reality, a verisimilitude of a peculiar and private sort. There was a romantic, secret quality to the stereo views, for one was privy to a sort of frozen theater when one looked through the eyepieces – a theater entirely one’s own. I felt I could almost enter into them, like the dioramas in the museum.