Controls in Black-And-White Photography

Richard Henry, Controls in Black and White Photography (1983, 1986) -- After a career as a much published researcher in clinical chemistry, Dr. Henry turned to photography. He was appalled by the lack of scientific rigor in popular books and articles written by non-scientific photographers. "They frequently make statements of fact which are totally unsubstantiated and sometimes utterly absurd." So he equipped his laboratory with sophisticated testing equipment and set about checking much that is commonly "known" about photography. "Nearly all the experimental work performed for this book was done with step wedges, etc. -- not pictures. In most instances, but not all, a picture actually gets in the way of accurate measurements that need to be made regarding the performance of film and paper." Following good scientific practice, Dr Henry mentions assertions of others, cites references, describes his experiments so others can replicate them, and reports conclusions. This is a refreshing contrast to the approach of writers who imply that because they are excellent photographers, readers should believe their unsupported opinions. Among the findings that contradict popular myths are:
1.The maximum black a paper can make does not depend on its silver content.
2.There is no difference in print values produced by condenser and cold light enlargers if negatives for the latter are developed longer to make print contrast the same.
3.Prolonged print development in Dektol does not increase contrast; it only makes a print darker.
4.Dissolved solids, such as silver salts, do not sink to the bottom of a print washer.
5.Amidol does not produce darker blacks than Dektol 1+1.
This book is extremely valuable for anyone who is seriously interested in making black-and-white photographs -- especially from small negatives. It is a special joy for already well-informed photographers to find so much new information.