Measuring light with meters
Photography is all about light. How you measure that light for your digital photos, using various light meters, brings different results to the digital images you capture.
The first step in figuring out what settings to use to take a photo is to measure the light. An accurate light measurement makes choosing exposure settings on your digital camera much easier.
Two methods used to measure light are employed by the following types of light meters:
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Incident meters measure the amount of light falling on a subject and work best when held in front of the subject and aimed at the light source.
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Reflected meters measure the light that is being reflected off a subject and work best when you aim them at the subject. The built-in meter in your camera is a reflected meter. Reflective meters believe that the light they’re reading is an average 18 percent gray and can be more easily fooled by scenes with a lot of light or dark areas.
Here are your options for photographic light meters:
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Handheld light meters come in both incident and reflected varieties with some making both available on the same meter.
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A built-in light meter comes built into your camera and works the same way as the handheld reflective light meter — by measuring the brightness of the light in your scene. Most built-in light meters have three modes:
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Matrix metering breaks the whole scene into pieces and then takes the meter readings from those segments to build up a more accurate reading of the overall scene. Matrix metering works very well in most scenes and is the mode you’re likely to use most of the time.
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Center-weighted metering places more value on the light in the middle of your scene than the light on the edges but still measures the light from the entire scene. This metering mode was originally used mainly for portrait photography, where the subject fills most of the frame and the background isn’t as important. It’s a good choice in any case where your main subject fills most of the frame and is close to 18-percent gray.
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Spot metering limits the light reading to a tiny area in the frame and ignores everything around it. Spot metering is very useful when you have a critical area in your image that you want to make sure gets the right exposure and is close to 18-percent gray.
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Using fill flash to lessen shadows
Using fill flash adds a touch of light to any scene that you want to photograph and helps to get rid of unwanted shadows, like those that fall across the eyes of a person wearing a hat on a sunny day.
Fill flash comes in handy when you’re photographing any scene that includes a lot of light but little of that light falls on your subject. Use fill flash whenever your scene includes too much light in the background or the direction of the light causes shadows to fall across your subject.
Use your digital camera’s built-in flash or an external flash to add just a little light to fill in the scene by following these steps:
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Turn on the built-in flash or put a flash on the hot shoe of your camera.
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Reduce the power of the flash so you don’t overpower the existing light.
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Take a test shot.
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If you need to, adjust the power of the flash until the light from the flash just fills in the shadows and doesn’t overpower the existing light.
Adding a diffuser dome to your external flash softens the light and makes the fill flash look more natural.
For instructions on how to reduce the power on your built-in or external flash, see the camera and flash manuals.
Quick lighting fixes for common portrait photography problems
When using your digital camera to create portraits, chances are not all the subjects you photograph will be supermodels. You may need lighting to draw viewers’ eyes away from trouble spots or to your subject’s best features.
Here are some quick lighting tips to make the best out of any challenges that portrait photography may throw your way:
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All about the eyes: When shooting a portrait, always make sure that the eyes are in focus and well lit. Dull, out-of-focus eyes can ruin an otherwise great photograph, whether you’re photographing people or animals. If the eyes look dull, add a little fill flash to the image to get the light in the eyes or use a reflector to bounce a little light into the face and eyes.
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Glasses: Eyeglasses reflect light, causing a lot of problems in portraits. If the glasses can’t be removed, do a quick fix by moving the arms of the glasses higher up on the temples so the lenses angle downward slightly. The new angle of the glasses will reflect the light at a different angle and should fix the problem. If the glasses can’t be moved, try changing the angle of the light that is striking the glass; a small change in the light’s angle may help fix the problem.
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A little thin on top: Lights can cause unwanted reflections on the heads of people who are bald or losing their hair. Make sure that you don’t aim lights directly at the bald area, and use a soft box or other diffuser close to the subject to make the light as soft as possible.
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An extra chin or two: To reduce that pesky double chin, have your subject tilt his head up slightly and photograph down at him from a slightly higher angle, making sure the main light is up high. This technique creates a bigger shadow under the chin and hides that problem area.
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Some quick weight reduction: A low-key style, one with a darker tone overall, has more shadows that you can use to hide problem areas. By adjusting the light’s angle, you can use the shadows to hide and reveal different parts of the body, resulting in some instant weight loss.
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Out-of-proportion hands: When a subject’s hands are placed forward in the portrait, they can look bigger than they should because they end up closer to the camera. You can minimize the effect by turning the hands so that the sides face the camera. Light illuminates the edge of the hands instead of the front or back.
Shaping light with photographic tools
Several photography tools can solve the too-much or too-little light problem by modifying the light you have available or the light you add with flashes and strobes. You use tools like reflectors and diffusers to change the quality of light in your digital photographs.
Here’s a rundown of the tools photographers commonly use to modify light:
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Reflectors can be any surface that you use to bounce light back into your scene. A reflector can be a wall or a ceiling, or it can be a specially made tool for photographers, which usually comes in the form of a circle covered in a reflective material. Some are collapsible and can fold up to a fraction of their size. These reflectors come in a variety of colors:
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Gold reflectors change the color of the light to a warmer glow. The light ends up looking more like the light from sunrise or sunset, so it can cause color problems in the studio. Gold reflectors work best outdoors under natural light.
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Silver reflectors tend to reflect the greatest amount of light back at the subject and don’t change the color of the light.
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White doesn’t reflect as much light as silver or gold, but the light it does reflect is even and soft. It works really well for close-in work, both on location and in the studio.
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Mixed reflectors have surfaces striped with silver and white or gold and white. These reflect less light than their solid counterparts. They’re useful when you need a medium amount of light, with just a touch of silver or gold in the light.
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Diffusers reduce the intensity of light. You put them between the light and your subject, and they make the light softer. Specialized diffusers for shooting in the studio, called soft boxes, go over the light and produce a soft box of light. Another type of diffuser is called a shoot-through umbrella because it looks like an umbrella that you’d use to keep the rain off but is made from semi-opaque material.
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Gobo is the term for something (anything) that goes between the light and the subject and modifies the light. Following are some common gobos:
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Snoots are tubes that are used to aim lights. Snoots restrict all the light except for that in the exact direction the flash or strobe is pointed. The more constricted the tube, the smaller the resulting light. The longer the tube or snoot, the more defined the shape of the light.
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Barn doors are hinged flaps that you position on the sides of the light to control the spread of the light. They can be adjusted to control how the light spreads out.
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Grids go in front of the light and control the spread of the light in much the same way as a snoot. The size of the grid is responsible for the spread of the light — the smaller the holes in the grid, the tighter the light.
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