While I could literally write a book discussing and dissecting light scientifically, for the sake of your sanity, I’m not going to do so. I’d rather that you have a working knowledge of how light works and learn to master it, through practice, than a theoretical understanding without practice. So to keep it simple, there are four main characteristics of light. They are: quantity, quality, color and direction. Depending on who you’re speaking with, some of these characteristics may overlap, but for the purposes of keeping it simple, they’re divided accordingly.
QUANTITY / INTENSITY
Quantity refers the to intensity of the light you’re introduced to, whether that’s natural or artificial light. It’s simply a term used to determine how much light you have in a scene.
By introducing more lights in on set, you’re affecting the overall contrast of an image. For example, if you have well defined shadows in an image by using one light, adding a second light to the shadow areas of that image will reduce the overall shadows and directly influence the contrast in your image. Remember that contrast is the difference between the highlights and shadows in your image. The less of a difference between your highlights and shadows, the “flatter” your image will be.
Also note that another way to make a light appear brighter is to move it closer to your subject. For example, if you hold a flashlight within a couple of inches from a wall, it’ll appear brighter than if you move farther away. This change will simultaneously impact the quality of light (see Figure 1.1 as an example).
Because there isn’t a quantitative way to score light quality, we simply define the quality of light by discussing how “hard” or “soft” it is. You’ll know that you’re working with hard light when your images have well-defined shadows and lots of overall contrast. The shadows in “soft” images will transition to areas of light without definitive lines of shadow.
Hard light is typically considered “bad” light, because it draws more attention to blemishes and wrinkles in the skin due to the overall contrast. This can lead to subject’s looking inherently older than they truly are. In addition to this, you’ll also spend more time retouching images, if you plan on working on your images in post production.
So where does hard light come from? The answer to that question is the secret to learning how to effectively control light:
The Quality of Light is Directly Influenced by the Size of the Light Compared to Your Subject Matter.
In laymen’s terms, the bigger a light is compared to your subject, the softer that the light will be. The smaller the light is compared to your subject, the harsher it will be as you can see in Figure 1.2.
Consider this. Let’s use the sun as an example. Comparative to the earth, the sun is a huge source of light. Because the sun is 93 million miles away (Thank you Wikipedia), it’s comparatively smaller in perspective to the earth. Don’t believe me? In the sky, the sun is relatively small compared to our large planet. This is why during the harsh midday sun; you have well defined shadows – it’s a very hard form of light. If we could decrease the distance between the sun and the earth (and survive), the sun would be larger in relatively to the earth. It would then fill in the shadows under your eyes, nose and chin. The easiest way to understand this is to remember that:
Shadows are created by the absence of light.
Studio strobes, speed lights and constant lights are generally smaller in size relative to our subjects. This is why we use lighting modifiers. They broaden the source of light and fill in any unwanted shadows in our images. On a cloudy day, the clouds act as a huge diffusor of light. It spreads out the light from being extremely directional and softens the light. That is why cloudy days make for amazing portrait sessions!
Later we’ll discuss how to take that same concept and apply it to taking photographs on location and in the studio. Understanding the difference between hard and soft light will save you both time and energy when you’re trying to find a location for a photoshoot.
What?! Light has a temperature? Yes. Yes, it does. This is probably the one thing I struggled with when I first started learning photography and now I can’t help but notice the difference in color temperature EVERYWHERE I go. If you’re willing to lose your sanity, keep reading.
All light is not equal. e.g. a candle produces warm light, while a fluorescent light emanates a cool light. Similarly, the color of light outdoors will shift depending on the time of day, weather conditions and a variety of other factors. Light is measured on the Kelvin scale, which is a standardized measurement of color.
In short, the greater the number on the Kelvin scale, the bluer cast a given light source will have. Adversely, a light source with a lower number will have more of an amber cast or a warmer tone as you can see in Figure 1.3.
Adjusting your White Balance, simply means that you’re adjusting your camera to record colors as they appear to the naked eye. You’re ensuring that the color in your images matches the colors exactly as they appeared in your scene. Now, our naked eye will automatically adjust to compensate for color shifts. Our brain quickly adjusts our eyes, so that we perceive different color temperatures as neutral, regardless if they are cool or warm.
Our cameras however, aren’t as intelligent. While Auto White Balance will generally do a sufficient job correcting White Balance, there are times when you’ll need to control your White Balance manually. This is especially true if you’re photographing a scene with different color temperatures or using artificial light, such as strobes or off camera flash.
Throughout my workshops and lectures, I will refer to color temperature and white balance. Use the information in this section as a reference to find the correct White Balance Presets that you’ll find on most DSLRs:
AUTO – Works well at evaluating color temperatures between 3,000K – 7,000K, but if you’re shooting with studio strobes or speedlights, the algorithm will not recognize this change. Additionally, if there is an abundance of one color, the algorithm will not know how to correctly balance that scene.
TUNGSTEN – Used when photographing tungsten light or if you want a blue hue to your images.
FLUORESCENT – Used for ‘cool’ Fluorescent artificial light.
DAYLIGHT / SUNLIGHT – Best setting to use in the bright sunshine, however slightly cooler than noon sunlight.
CLOUDY – Best used when the sun is behind the clouds and can also be used some shady areas.
FLASH – Used when photographing with an external speedlight or studio strobe.
SHADE – Used to photograph shady areas or some sunset shots. This can also be used to help you introduce warmer colors in your image.
PRESETS (PRE) – Used to match a white or grey card.
IMPORTANT NOTE: The best solution is to set correct White Balance is using the RAW file format. This will allow you to convert to any white balance in post production, because the original image is unprocessed by the camera.
The direction of light refers to where light is coming from and directly influences the shape of the light in your scene.