True Black and White Prints From Digital

Fifteen years ago (1990) I thought the greatest barrier to digital photography would be printing, and I thought quality black and white printing was probably just around the corner. After all, I could produce recognizable grayscale images on a 300 dot-per-inch (dpi) laser printer. Can the 5000 dpi laser printer be far behind? The reality is that colour ink-jet printers have developed faster than I had ever imagined. True photographic quality inkjet printers not only exist today, but are surprisingly low in cost.
Current colour inkjet printers probably have sufficient resolution to produce decent grayscale prints - we'll discuss a caveat or two a bit later - but the results are often less than convincing. While inkjet colour prints generally appear to be as good as or better than traditional colour prints, typical inkjet grayscale prints will not be mistaken for their traditional silver-chemistry-based equivalents. The problem area is, ironically, image colour. There are at least three colour problems, but all of them stem from the fact that our eyes are remarkably critical of near-neutral colour and colour differences. The three problems might be called image tone, variation of image tone, and metamerism.

Image Tone

Traditional black and white images are seldom - if ever - neutral gray in colour. They tend to be yellowish or brownish. The papers used for black and white prints too tend to be yellowish. There are lots of variations. Although the average person is not consciously aware of the tone of traditional black and white prints, the experienced photographer will often be able to look at a print and make a pretty good guess about the paper's manufacturer, the developer used and any specific image toning that was done. It's rather like recognizing fine wines; the differences can be obvious or extremely subtle, but the factors needed to distinguish one from another are quite definitely there. Getting that tone right with Photoshop and an inkjet printer is not an easy task. Still, who is to say what the 'right' image tone is. It comes down to preference. And maybe someday we will all agree that grayscale images look best with a tone that cannot be achieved the traditional way.