Harold Merklinger is a retired scientist living in Dartmouth, Nova Scotia. As a teenager he considered photography as a career, but after talking to a few professional photographers, he decided that there were probably other careers that would afford a better chance to appreciate photography as a hobby. His interests tend to be somewhat technical. In 1990 he wrote a book on photographic depth of field and followed that with a second one in 1993 on view camera focus and depth of field. Both books are currently available for download from his web site:http://www.trenholm.org/hmmerk/download.html