Because it is rather on the technical side for me (I have never taken a photography class or read a photography book, other than my camera manual [Panasonic DMC-FZ50]), I wanted to review the chapters I've read thus far for myself, and I figured while I was at it, I might as well begin a long book report. Although Adams discusses film photography rather than digital, most elements are also applicable to digital photography (and you'll have to forgive me for skipping over those that are not).
Chapter 1 Visualization and Image Values
Adams discusses the process of visualization: "a conscious process of projecting the final photographic image in the mind before taking the first steps in actually photographing the subject" (p. 1). Although his work is considered "'realistic,'" he "employ[s] numerous photographic controls to create an image that represents 'the equivalent of what I saw and felt' . . . " (p. 1). This helped me see why my "point & shoot" theory is so haphazard. I need to "become aware of the world . . . in terms of a photographic image" and look for "significance, substance, shape, texture, and relationships of tonal values" (p. 2). Adams suggests three items to look for in a subject:
1. The darkest significant part.
2. The lightest significant part.
3. Visualize the middle of the scale.
Because his emphasis is black & white photography, this involves mentally converting the values to various shades of grey, and "becom[ing] aware of light and tonal values in terms of print values" (p.3). Next come the technical, photo-taking steps of "measuring the luminances of the subject and using this information to determine exposure and development, and considering possible further means to control or alter the values in accordance with our visualized image" (p. 7). We must learn to see intuitively as the lens/camera sees, and to understand how the negative and printing papers will respond" (p. 7, emphasis added).
Chapter 2 Light and Film
Adams tells us that what we see in terms of image values is not what the camera sees, because we perceive electromagnetic radiation (400 to 700 nm, particularly) differently. He defines different types of light, as follows:
Incident light: or illuminance is light cast on a subject from the sun, sky, or bulb (measured in units of foot-candles).
Reflected light: or luminance is what we see and photograph (measured in units of candles-per-square-foot). A surface's luminance "is determined by the amount of light incident upon it and [its] reflectance . . . expressed as a percentage that indicates the proportion of incident light that is reflected by that material" (p. 12). The relationship of this light and the visualized print values determines the outcome of the photograph. Reflected light may be one of the following:
Diffuse reflection: light is reflected equally in all directions from a matte surface.
Specular reflection: light is reflected as a beam in one direction from a polished surface.
This chapter also covers film qualities.
Chapter 3 Exposure
A hypothetical perfect negative would be "one exposed and developed in specific relation to the visualized values of the functional or expressive print" (p. 29). A definition to help achieve this end:
Exposure = Intensity x time (E = I x t), because film can be given equal exposure "using relatively high intensity of light for a short time, or less intense light for a longer duration" (p. 30). For example, open the lens aperture one stop more and reduce the shutter speed by half, and the net exposure is the same. So in the end, the term indicates "the camera aperture and shutter speed used" (p. 30). Exposure meters are discussed, and I'll summarize with Adams' statement that a meter "reading made from any uniform luminance surface used directly to determine exposure will give exposure settings that will reproduce that surface as a middle gray in the final print" (p. 33). He also points out that "it is better to overexpose slightly than to underexpose" (p. 37). I found the exposure corrections section somewhat confusing, so I have to study it further before I can report it here.