Some of the theory is good, and many myths are debunked. In my opinion the first half of the book which deals more with printing (paper etc) is perhaps the better part of the book - although the materials themselves are all outdated except Dektol. I find the second half a little more difficult to follow. Exposure theory, K factors and meter calibration etc - these are not the clearest parts of the book. And the film/developer testing data on granularity, sharpness etc are of relatively little practical use.
To me, the most important "learning outcome" from reading Henry is a healthly skepticism. It reminds us much of what we read about photographic technique and materials has little in the way of evidence to back it up. And as Stephen has said many times, even when we are presented with data it is important to be given information on the testing procedures, otherwise it is difficult to conclude anything. Sometimes you read an article in a magazine and it looks really sound because is has tables and charts and curves. But what if there were all sorts of errors or sources of error, mistakes etc in the test? As we know there are many variables to manage, and as I've come to learn, designing a proper photographic test is not so easy.
At the same time though, once we realize how much of what people say is wrong - including some very fine photographers/printers - we must then reconcile this to the fact they still end up with great prints. This tells me there is quite a bit of lattitude in the photographic process, from metering to exposure to development to printing. It means people can be wrong about what is going on at a scientific level but still make things work, because the lattitude provided by our materials allows them to work around the "data" they present with practice - usually without them knowing it. Often, people, even great photographers are not getting what they think they are getting from their process when it comes to film speed, curves etc, but it doesn't really matter because with practice they've simply developed their technique around what they are actually getting.
Stephen has written about all this before, so I'm not saying anything new. I just like Henry's book because it presents many practical examples.
To sum things up, there is a lot of bad information out there. Just because someone on APUG, or the author of a book says something is so, doesn't mean it is so. When somebody makes a statement, you might ask them to prove it!
Last edited by Michael R 1974; 02-01-2013 at 07:20 AM. Click to view previous post history.