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Notes on Lighting
by James D. Blodget
Light is the photographer's medium. Photographers use light as artists use charcoal, ink, or paint. It is as important for the photographer to learn how to manipulate light as it is for the artist to know how to mix and apply paint.
When light falls on an object, some is reflected and some is absorbed. Different surfaces appear different under the same source of light, because not all surfaces reflect and absorb the same amount of light. Also, the same surface will appear different under different kinds of light.
Light sources differ in area, brightness, color, coherence, duration, and beam spread. Examples of different light sources include: sun, sky, flash bulbs, strobe (electronic flash), photoflood, quartz/halogen lamps, household bulbs, florescent bulbs, and flames.
Studio lights come in two basic kinds - spot and diffused. There are four uses of studio lights:
Properties of light:
Intensity is the brightness of the light. Basically you need enough intensity to expose the film properly.
Color is the frequency of the light. The brain compensates for different colored light sources. Humans are color-adaptive. Film and video are not. You need to match the color of the light source to the color balance of the film.
Daylight film is balanced for 5400 degrees Kelvin.
Coherence is the hardness or softness of the light source. Coherent light is a hard and directional light which casts sharp, deep shadows which bring out texture. A laser is the ultimate coherent light. Diffused or reflected light cast soft shadows which minimize texture.
Controlling the light:
Shadow patterns are created by the main light. Choose patterns which show the best shape, create the best ratio of light to dark, and show the appropriate texture. Look for a single directional light source. Gradients of brightness create depth and shape.
Contrast is the difference between the darkest and lightest portion of the scene. Bring the contrast down to a level that the film can record. Match the contrast level to the subject mood. Contrast can be modified by controlling the intensity of the highlight or the density of the shadow.
Separation is created by differences in brightness.
Reflections off shiny surfaces such as glass and metal can often be controlled. Spectral highlights can be eliminated by using a diffused large area main light. White, black, gray, or colored cards or other objects can be used to create controlled reflections.
Light in perception:
1. Gradients of brightness create depth and shape.
2. Distribution of brightness helps to define the orientation of objects in space.
3. Brightness is relative. The observed brightness of the object depends upon the distribution of brightness values in the total visual field.
4. Usually the observer is not conscious of the source. Light seems to be a quality of the subject. The object appears to have a certain brightness and color.
5. Shadows are not part of the object, but are rather thought of as a thin, transient film.
6. Dark shadows may destroy shape. Shadows maintain their character of a transparent film only when their borders are blurred gradients. Dark, crisp shadows may hide relevant portions of the object and/or destroy the continuity of curvature by creating sharp boundary lines between brightness and darkness.
Use daylight as a guide to studio lighting (top light, one single light source which casts distinct shadows, and diffused fill light from sky and surroundings).
Common problems using studio lights:
Follow these basic steps:
I. Place the subject and the camera
First, determine the approximate position of your subject in relation to his or her surroundings. Then choose the camera angle, distance, and lens combination to secure the proper framing and depth of field.
The focal length of a portrait lens is about two times the diagonal of the film.
2 1/4 film uses 135mm or 150mm lens
Turn subject's shoulders about 45 degrees to the camera. Put a table under the back arm (this gives the person security and lifts the back shoulder). Point the nose towards the edge of the camera. The head should be tilted slightly towards the back shoulder.
Posing a 3/4 figure (female):
Cross the near knee. If the girl is slender, show both sides of the waist. Bring the subject forward on the seat and arch the lower back slightly. Tilt the head towards the near shoulder. Look for strain in the shoulder. Try to stay away from the palm of the hand or flat of the back of the hand. Turn hand until the edge of the thumb disappears. Bend the wrist. Keep the thumb into the forefinger.
Try to avoid having the white of the eye show underneath the pupil.
Put the large eye closest to the camera.
To slim a face, put the tapering side next to the background.
Look at eyebrows, eyes, nose, mouth, chin, tapering of face.
Usually use a high angle to narrow the face.
Check the set-up through the camera.
Do not use a spot light as the shadows will be too hard. Use a diffused light.
Don't let the shadow of the rim of the glasses fall on the eyeball. Ignore highlights on rims of glasses.
II. Place the main light
The main light shows shape. Use a large directional light source which throws definite but soft shadows. As we take the light up we see more shadows, thus more shape. Don't let shadow cross the lip. In theory the nose shadow should be 1/3 or 2/3 of the way to the upper lip. Aim the main light at the chest, not the face. This evens up the lighting.
The main light is usually a spot light which should overpower any fill shadow.
Use a large area light source if possible.
Feather the main light to give roundness. Feathering means to turn the light in the direction of the camera so that the soft edge of the light is hitting the subject instead of the hard central core of the light. Turn the light until the fall off reaches the ear. This is how you achieve skin quality.
The main light can be placed on either side of the camera. In general there are two kinds of main lighting - short lighting and broad lighting. Broad lighting is when the main light illuminates the side of the face which is turned towards the camera. The face is lit broadly from the tip of the nose to the back of the ear. In short lighting the main light illuminates the side of the face turned away from the camera so that the face (from the camera's point of view) is lit from the tip of the nose to the far cheek.
There are five major locations for the main light:
Butterfly lighting is front lighting. The shadow of the nose is cast directly below the nose, but does not reach the lip.
Butterfly lighting slims the face and hides small skin imperfections and wrinkles.
In loop lighting the main light is placed a little to one side so that the shadow of the nose creates a loop shape.
Loop lighting widens a narrow face and lights up the eyes. Be careful not to distort the lips. Keep the nose shadow high enough so that when the person smiles, the shadow does not touch the lip.
Loop lighting opens up deep set eyes more than 45 degree lighting.
Moving the main light further to one side creates 45 degree lighting in which the light breaks over the bridge of the nose and creates a small triangle of light under the eye on the shadow side of the face.
If in doubt, use a 45 degree lighting. The bottom of the 45 degree triangle should be at the base of the nose. Either include all of the eye or exclude all of the eye. Never cut across the eye.
Split lighting is achieved by lowering the main light to eye level and moving it all the way to the side so that half the face is in highlight and the other half is in shadow.
Split lighting is character lighting. It picks up texture. It is also the most dangerous. The danger lies in contrast. Meter at 45 degrees so that both main and fill hit the meter. The main light should be slightly above shoulder level. Move in an arc until you see a spill. Then move back and feather.
Rim lighting is mainly used for profiles. The main light is moved around behind the subject, and creates a bright rim of light on one side of the subject (usually the profile of the face).
In rim lighting turn the subject until the far eye just disappears. Move the main until it spills. Then move it back and narrow the light with barndoors. Fill light for rim lighting goes on the same side of the camera as the main. Fill = 125 footcandles minimum. All you want is separation. Background light must be low. Keep fall off at level of chin. Use a fill to fill in the back of the head (use a reflector). You could use a mini spot with a snoot for your rim light. (150w bulb max.) Turn your subject's shoulder at a 45 degree angle to the camera axis.
If the rim on the nose disappears, the main light is too low. If the rim on the nose is too hot, the main is too high.
Watch out for a split profile where the nose goes past the cheek or touches the cheek. Also, look out for the bridge of the nose cutting into the eye.
You can do loop, 45 degree, and butterfly in profile.
General lighting tips:
Catch lights in the eyes should be at 11:00 or 1:00 o'clock.
When the highlight on the nose blends into the cheek, the lighting is too strong.
Use a gobo (a card which blocks light) to throw a shadow on an area (for instance, a high forehead or a white dress).
Flat lighting is the least flattering.
Use 45 degree or split lighting with men and butterfly or loop lighting with women.
Use high key with women and low key with men.
Let the ears match the background in men's portraits.
III. Control contrast
Fill light controls the highlight to shadow contrast ratio by reducing the shadow density.
The Fill light normally goes by the camera on the side opposite from the Main. This way any shadows it creates will be thrown directly behind the subject and will not be seen by the camera. Use a broad soft light for the fill. Fill for the butterfly is directly under your main. The purpose of the fill light is to lower the density of the shadows created by the main light. Contrast is measured in terms of the contrast ratio. Measure the intensity of the light on the highlight side of the face and compare it to the intensity of the light on the shadow side of the face.
Highlight = main plus fill
Shadow = fill
To achieve a 1:3 ratio measure the main light alone. Then work with the fill light alone until it measures 1 stop less than the main. (E.g.. main = f:11 and fill = f:8).
Best ratio in color photography is 1:2 or 1:3.
Often a reflector can be used as a fill or you can use a light with an umbrella.
Try to balance shadows in intensity. Use a reflector.
If you use a reflector as a fill, keep it parallel to the lens and use the front end of the card. Keep reflector fills at eye level.
On profile you need a cheek line. Work the fill around until you have a soft shadow.
The other approach to lowering the contrast is to lower the intensity of the main light by using a scrim or a neutral density gel between the subject and the main light.
IV. Light the background
The background light is usually a small light placed behind the subject which illuminates the background with a soft gradation of light from light at the bottom to dark at the top. To get a medium gray background light the background to the same intensity as the face. Gradation should break at the ears. Stop the lens down to f:16 and check separation. Use as a minimum a 250w light on a black background.
Look for harmony between background light and light ratio.
V. Create separation
A separation light is sometimes necessary to separate an area of the subject from the background. For instance, the hair may be the same value as the background. A hairlight should be slightly more intense than the highlight on the forehead. Check the hairlight to see that it's not spilling on the face or the shoulders or the ears.
Use kickers (mini spots with snoots) to highlight the temples. They should be placed behind on either side of the subject 24 to 30 inches away. The light should miss the ears and the nose.
VI. Determine exposure
The whole purpose of balancing your lights (controlling the contrast radio) is to produce a subject brightness range which your film can handle with normal exposure and development. So, use one of the following four methods to determine normal exposure:
Expose for the highlight (main plus fill).
Standardize your meter reading. Meter on the highlight side down by the chin. If you are using a built-in or hand-held reflected light meter, use the reading off an 18% gray card or meter off the back of your hand and open up one stop. Hold the meter 1/2 the length of the diagonal of the card away from the card. Watch out that you don't cast a shadow or reflect more light onto the gray card with your body or clothing.
If possible, stay at an aperture of f:8 or f:11 and a shutter speed of 1/8 second or above.
Shutter speed should be at least 1/100 second in color.
To get skin to pop, underexpose and overdevelop (in black and white).
When focusing, check both the eyebrows and the lips. Depth of field should include from the tip of the nose to the back of the ear. Also, check to ensure that the hands are in focus on a 3/4 shot.
Don't hit glass with raw light. Bounce light at 45 degrees off a white background so that the light comes through the glass or use a broad light behind a translucent material (again lighting the glass from behind). Another approach is to use a black background and to rim light the glass with two lights. This will give a white rim against a black background. Also you can use a white reflector on one side to give a faint white outline on that side. Shoot two exposures. Open one up one stop and the other two stops. Look for a black line all around the rim and get good whites.
You are photographing, not the metal, but reflections of what's around the metal. Use a white tent. Gather cloth around the lens. Or use a cone and shoot straight down on the subject. Or use cards to create a baffle box. Cut a hole for your lens to peek through.
Watch for separation. Use high main. Give yourself room. Avoid dark areas. If white highlight blends with the white background, put a gray or black card to the side so that the metal picks it up. Or use grease pencil and draw a line on one side of the object for separation. Or use chalk for a highlight.
Exposure - no heavy shadows. Print them light. Go one and two stops over.
Evaluating Your Work
Critiquing lighting in a print:
Look at highlights in skin. There should be detail. Highlight should not block up.
Negative and print quality:
A good portrait negative should be thin with good detail.
Try to make flash look like available light. Always check out your sync by flashing through the camera. It's better to have the flash high above the camera rather than just to the side. That way the shadows will fall behind the subject.
When using bounce light, use a manual flash setting, figure the distance traveled, and then open up a stop. Bounce out of a corner if possible or off a wall behind you.
Flash fill: put flash by the camera. If shooting at 1/125 at f:11 for example, find the distance your flash will need f:11 (let's say it's 4 ft.). At 5.6 ft. you'll have a 1:2 ratio and at 8 ft. you'll have a 1:4 ratio.
To use your flash as a main light bring the flash in closer than 1:1 distance. Put the flash to the side. (In the above example set the flash at 2.8 ft. and expose at f:16).
2001 James D. Blodget