"Beyond" the Zone System

Berin Loritsch — Mon, 22 Jun 2009 12:14:00 +0000

In the process of trying to coerce a working system in my darkroom, I purchased the book “Beyond the Zone System” because I know it has a lot to help understand sensitometry. What appeals to me is the ability to both test the speed of your film and the development time within 6 sheets. Since Ansel Adam’s film speed test takes seven sheets and an unknown amount of sheets for the dev test (at least one but in practice a few more), I’m all about conserving resources. The cost of the sheet of film is only one part of the cost—it’s the investment in time that I’m most concerned about.

BTZS starts out with a nice little overview of how paper and film work together to make the finished image. It also has a review of all the types of math and graphing theory that pertains to this testing process. The math’s not that hard, but the problem is in the way it’s presented. You can tell the author has a wealth of information, and he tries to make it accessible all in one or two chapters, but you almost end in confusion.

Where my head really starts swimming is when he gets in to calculating film speed. With Ansel Adams, it’s simply a density of 0.1 over film base+fog. The author covers the history and the pros and cons of how film speed was calculated over time, instead of just choosing one and teach how to do that one. It’s useful information, but the alternatives could be moved to an appendix to make that section more accessible.

With a proper handle of the basics of how the film and paper relate to each other, you can intelligently make decisions on exposure, development, and printing decisions. The road to understanding taken in the BTZS approach is very technical, which is not for the feint of heart. However, once you’ve learned the basics, you learn useful bits of information. For example, changing development times is similar to changing apertures—they both follow the same geometric progression of numbers (4, 5.6, 8, 11, 16…) to produce the same changes in final density. Shutter speed times and film speed numbers follow the same progression of numbers.

If you are serious about understanding more about how your materials work and respond to light, this book is definitely something you should have in your library. It will take time to “get it”, but once you do it will help you with your final results. You have a better understanding of why you choose a particular density for your print materials. You also have a better understanding of how zones don’t equal stops of exposure—yet the two still relate predictably.

Just a Thought...: Tag book

"Beyond" the Zone System