6.13. How to use this simplified system when using black and white negatives?
Although I do not want to get too deep into this subject, the following are the most important differences between slide and black and white film.

6.13.1. The Film Contrast Range (FCR)
For practical purposes, the FCR of black and white films used by many photographers is around seven stops. This compares with the FCR of five that we used throughout this book with slide film.

6.13.2. The Reference Tone
In this book, with slide (positive) film, we selected the medium to brighter (whiter) portion of the subject to be used as our Reference Tone. With negative film, as the name implies, the selection is exactly opposite. In this case, we select the medium to darkest area of the subject (lowlight) that we are interested in capturing detail.
The logic behind this is simple. By choosing the lowlight portion of the subject as a Reference Tone, depending on the degree of the desired detail, we can place this tone into any of the darker
zones of our Tone Ruler. These include 2.25% or 4.5% zones. While concentrating on the lowlights of the subject, for a subject with a long tonal range, there is a good possibility that we will produce overexposed highlights on the negative.
The philosophy with this technique is that "overexposed highlights are better than underexposed lowlights" or simply said "with overexposed highlights, you have always something to show for where with the underexposed lowlights you have nothing."
The following is a summary:

OVEREXPOSED HIGHLIGHTS:
Although overexposed highlight may go off the film's seven-stop FCR, they will have enough details that can be forced out of the negative in the darkroom.

OVEREXPOSED LOWLIGHTS:
Lowlights that can be placed in the 2.25% or 4.5% zones of the ruler will record on the film and retain marginal detail so that they can be printed in the darkroom.

UNDEREXPOSED LOWLIGHTS:
This is perhaps the worst nightmare of a photographer. With underexposed lowlights (underexposing the black and white negative causes this), there is no recorded detail on the negative that a photographer can print. These areas will be totally black and are least desirable.

The confused photographer's guide to photographic exposure and the Simplified Zone System by Bahman Farzad covers the Simplified (5-stop) Zone System, Incident metering, spotmetering (spot metering / Partial Metering), Pentax Spotmeter used as example) Misc. exposure techniques from Sunny-16 to Moony-64.


Copyright 2002, The confused photographer's guide to photographic exposure and the Simplified Zone System by Bahman Farzad