Toronto. The post title must be a favourite of mine – used many times here, Long before digital photography arrived where it is today, professionals and advanced amateurs struggled to make prints that gave the most accurate and satisfying monochromatic rendering of their subject. Film, paper grade, paper surface, developers, and lighting all played a part in the matching of the subject to the final print (plus a dash of artistic talent thrown in for good measure).
The combination of all this marvellous magic culminated in the science of Sensitometry. We see a vestige of this today in the H&D curve displayed on the back of some digital cameras indication the proportion of dark to light areas in the image. Browse the Encyclopedia of 19th Century Photography for their explanation of Sensitometry and many other fascinating articles. This book was published in 2008. The pdf here is courtesy of the website, Archive.org. A hard copy is available with free shipping for a modest $676 USD.
Most people who use a smartphone camera today seem content to let the computer in their phone determine the various elements that combine to make a reasonably accurate image of the subject (and a very good determination it does, indeed). In the 1950s-1960s we didn’t have such a luxury hence the interest in Sensitometry, and the books that taught us the technique of choosing the variables that ended up making a good monochrome print of the subject.