Light Ch 1, 2, & 3
In chapter one of Light- Science and Magic, the author emphasizes the importance around understand lighting and when photographing. They mentioned three principles of lighting. The first was that the size of the light source is the most important decision. It influences the shadows that will be cast and potentially the type of reflection that appears. Secondly, there are three types of reflection that are possible from any surface, which determines why a surface looks a certain way. Third, some reflections only occur if the light strikes the subject within a limited family of angles, meaning this family of angles will influence where the light source is placed. The author then goes on to talk about concerns some students may have when learning photography. One is the issue of equipment. However, as the author describes, it is the photographer, rather than the equipment that is most essential in the production of a successful photograph. Furthermore, with creativity, lighting obstacles can be overcame, and most projects can still be done well without expensive equipment. That being said, it is important to anticipate these obstacles and decide how to work with them.
In the second chapter, the author goes into the more scientific and technical side of light. They explain that light is a type of energy called electromagnetic radiation, which travels in photons. An electromagnetic field is created by the energy of these photons. These fields have different frequencies, which we see as color. A roughly even amount of red, green, and blue light is translated as white in our brains. However, our cameras aren’t as skilled, which is why we have to adjust the white balance in post. They go on to say that brightness is the most important quality of a light source. Unless one is looking for a specific aesthetic improvement in contrast or color, typically brighter is better. You should be able to identify a high contrast light by looking at the shadows. If the light’s rays strike the the subject at nearly all the same angles, there will probably be hard shadows, and therefore the light will be high contrast. Inversely, a light that has soft shadows will likely have its rays hitting from different angles, and will be considered a soft light with low contrast. For single light sources, the size will be the main factor in determining the contrast. The difference in lighting within a photograph often has to do with the subject rather than the light itself. Subjects can transmit, absorb, or reflect photons, meaning that the light we see in a photograph is based off of how the subject influences those photons. Lighting, as the author states, is a relationship between the light, the subject, and the viewer.
In the third paragraph, the author dives deep into reflections and how to manage them. There are three types of reflection: diffuse, direct, and glare. Diffuse reflections are reflections that are the same brightness regardless of the the angle we view them at. White subjects, for instance, produce a lot of diffuse reflection. If you viewed it from any angle it would likely be the same brightness. Only once you adjusted the distance of the light source would the brightness change. The Inverse Square Law, is responsible for this change in brightness. The law states that a light from any distance from the subject will light the subject with an intensity that is inversely proportioned to the square of the distance. For example, a light source will light a subject with an intensity nine times as much as a light source that is three times its distance away. Direct reflections are mirror images of the light source that produces them. The family of angles determines when a direct reflection can be seen. The light source, subject, and camera viewpoint have to line up in such a way to capture it. The Inverse Square Law does not apply to direct reflections. The brightness is unchanged by the distance of the light source. Polarized reflections are similar to direct reflections but they are significantly less bright than the light source. These are more apparent if the subject is black or transparent, like a lake or plastic. Most subjects produce a mixture of both. It is important to have this understanding of the relationship between light and subject, so as to prepare for appropriate lighting.
