Welcome to Photography Course #1
When it comes to light and photography, its helpful to understand some of the basic physics behind light and lenses. The word “photography” was created from the Greek roots (phōtos, phōs, and graphé) which together means “drawing with light”. It is important to remember that light is the primary working tool of any photographer.
Light is the visible portion of the electromagnetic spectrum that starts from red (the weakest of rays), all the way to violet (which is the strongest of rays). Light rays from the sun are considered white because they contain all the colors of the spectrum. Black is simply the absence of any color.When we place a prism in front of a white light ray, the prism will diffract (or separate) the ray into all the colors of the spectrum.
When we place a LENS in front of any ray, that lens will simply refract (bend) that ray.
A camera lens is ground or molded transparent material (glass or plastic) that refracts light rays to form an image. A lens focuses light onto the sensor of a digital camera to create an image. It is also known as an optical or photographic lens.
Creating an Image
As a light ray enters the lens, it is refracted and exits the lens refracted in the same manner. Because of the geometric shape of the lens, light rays are refracted so they form images. So when we place a LENS in front of any light ray, the lens will simply refract or bend that ray. Being in focus simply involves moving the lens elements forward or backward until all the rays coming toward the camera from the subject meet at one point; the camera sensor. In the illustration above, you will see a point where the rays meet. That point is also called the film plane. At that point, all light rays of the subject must meet to accomplish sharp, focused pictures.
Photographers are constantly talking about the quality of light (both good and bad). Light can be hard or soft, direct or indirect, natural or flash, and come form different angles. As you start to learn the Art of Photography, you will undoubtedly hear photographers refer to using “good light” in their photos. So what is good light? There is no one good answer because it’s subjective. Good Light is just the right amount, quality, color, and angle of light a photographer needs to produce a desired image. For a landscape photographers shooting in the early evening, it’s all about timing for the best light. The Golden Hour is the hour between sunset and nighttime when the light is diffused, soft, and colors can be vivid. This is in comparison to daylight which is harsh, leaving subjects looking flat and unflattering.
Types of Light
There are generally three types of light sources in photography;
- Flash (on camera)
Quality of Light
When photographers talk about the quality of light, they’re referring to the intensity and direct of light;
Angles of Light
The angle of light is the direction of your light source;
- Diffused (or dispersed)
- Night (or twilight)
NEXT STEP: Lesson #2: Light and the Human Eye
You’ll learn that your eyes combine colors differently than colors are combined when painting.