In my crusade to learn more about photographic chemistry I visited the US, UK and German versions of Amazon’s second hand scene and went on a book buying spree. One of the books that I purchased is “A textbook of photographic chemistry” by D.H.O. John and G.T.J. Field, which was published in 1963. I bought my copy from Amazon.de for less than 9 euros in okay condition. The binding is reinforced with clear tape, the dust cover is missing and it contains some markings, but nothing that spoils it from being a decent read. Although it may be annoying to read in the beginning, with many forward references, it makes a good addition to the darkroom library and elucidates many concepts. Below you can read why.
As the preface outlines, the book is intended to bridge the gap between the research laboratory and the practical workman, by explaining the entire photographic process from beginning to end. The book contains 330 pages in total, of which 290 are of interest to the darkroom printer that wants to understand the chemistry of the processes he or she uses. The last 40 pages are dedicated to the final chapter, which is nothing more than a list for further reading, the appendices and the index.
The focus of the book is on the formation and the development of the image. The discussion on this starts right away in chapter 1 , which is titled “The Problem Explored”. The history of chief methods using the action of light to form an image is outlined. They skim over the historic processes of bitumen prints and collodion processes, and spend more time on the most prevalent silver bromide process. The underlying chemical concepts are introduced and the process is compared to its predecessors. The title of the book contains the words “photographic chemistry”, and it should therefore not be surprising to find simple chemical formulas in the first chapter. These are, however, nicely explained and should not pose an obstacle for the reader that has only an elementary understanding of chemistry.
I highly recommend reading chapters 2 and 3 of this book, which are titled aptly “The Emulsion Designed” and “The Emulsion Exposed”. These two chapters have been instrumental in preparing the recent post on the science behind reciprocity law failure and provide and excellent explanation of why the emulsion is constructed the way it is and the formation of the latent image. They are followed by chapter 4, “The Emulsion Mishandled”, in which the authors discuss the unwanted effects that occur before exposure, during exposure and after exposure. Most of these are of mere academic interest, others, such as the reciprocity law failure and Russel effect can also of practical concern today.
The fifth chapter of the book, “The Developer Compounded”, complements the typical formulae books by providing insight in the chemical composition of many developing agents and their related compounds. Although high school chemistry should suffice to understand the larger part of the terminology, a better understanding of chemistry is required to be able to grasp more advanced concepts in the first part of the text. I found many terms are not introduced and the reader is assumed to have knowledge on reading chemical formulae and potentials. However, this only covers part of the chapter as a considerable larger part is aimed at exploring the differences between certain developing compounds and explaining the chemical processes that turn the latent-image into a visible image. The more practical aspects of developing are explained in the chapters titled “The Developer Employed” and “The Developer Controlled”.
Chapter 8, “The Image Produced”, is focused on fixing the image and the underlying chemistry, use of the stop bath and its importance, and washing. Chemical intensification and reduction are briefly touched upon, but other resources provide more information on these processes.
Chapter 9, “The Image Examined”, is often referred to in the prior chapters, as it explains important concepts such as density, gamma and speeds. If the most important concepts of this chapter had been explained where they were first referenced, the text would have made much easier to read. However, this chapter is much more extensive in explaining these concepts than I have encountered in similar works, which makes for a clear and comprehensive reference.
The 1oth and 11th chapters concern more practical aspects of enlarging systems and their possible weaknesses. The authors introduce the reader to concepts as contrast ratios, selection of the right paper grade, and how to store prints to limit the effects of ultraviolet light and physical damage. The discussion of paper grades is largely outdated, as variable contrast papers are ambivalent in today’s practice.
As this book is of 1963, Chapter 12 is largely obsolete and only of academic interest. “The Problem Unlimited” lists many journals in which research was published at the time. Many of these, however, ceased to exist over 20 years ago and the larger part of it is either behind a paywall, or has not been digitized (yet).
In their attempt to produce a linear story from the physics and chemistry of image formation to the making of a print, many concepts are omitted in the beginning that would be useful for the understanding of the reader. Many forward references are included. John and Field use terms like density and gamma without introducing them first and instead refer to a section 200 pages further in the book. Especially in the beginning this makes reading the book rather annoying. Reading the first few chapters of Jacobson and Jacobson’s “Developing” (click here for the review) helps a lot.
At the end of every chapter, a reference list is included, which I find a great advantage over the previously mentioned title for research purposes. As I purchased these books to better understand the processes and aid in writing the articles for this blog, I find it useful to have access to the original manuscripts.
Although the book is not without its flaws, I find it a nice addition to my library and I learned a lot about latent image formation and the developing process. It offers clear explanations on many issues that I have not found elsewhere and is a great starting point for further research in most of the topics that are discussed. As you can pick up a decent copy of this book for less than 10 euros including shipping, I recommend that you add it to your darkroom library too.
About the authors
Details about the authors are hard to find. When the book was published David Hugh Oakley John and G.T.J. Field were employed by the research laboratories of May & Baker Ltd., a British chemicals company that manufactured photographic chemicals amongst others. David (co)authored at least two other books in 1965 and 1965 on photographic processing and techniques for photography on expeditions.