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MSC 258 Multimedia Presentations

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1 MSC 258 Multimedia Presentations
Lighting With Excerpts and examples from: Photography 8th. Ed., London, Upton, Stone, Kobré, Brill, Prentice Hall, Upper Saddle River, NJ, 2005

2 “Light is the very substance of photography, and it’s knowledgeable use is the basis of the photographer’s craft.”* Changes in lighting will change your picture. Outdoors: Natural lighting (daylight, starlight, sunlight) Indoors: Artificial lighting (existing, continuous, flash) Existing: Natural and/or Artificial already present in a scene. Most photographers prefer natural light. However: Natural light is usually uncontrollable. Can’t be moved and it is subject to the whims of weather. Natural light is not always available – indoors, night, etc. Sometimes, you must choose between adding an artificial light source, or not taking the desired picture at all. *Alfred A. Blaker Handbook for Scientific Photography Photography: Art and Technique

3 The Direction of Light: Consider Your Alternatives
Back Lighting The light comes toward the camera from behind the subject. Front Lighting The light comes from behind the camera toward the subject. Side Lighting The light comes toward the side of the subject and the camera.

4 Lighting Contrasts: Consider the Results
Direct/Hard Light Creates hard-edged, dark shadows. Fully Diffused/Soft Light Provides an even, soft illumination. Shows little or no directionality. Shadow edges are light and indistinct. Directional-Diffused Light Combines qualities of direct and diffused light. Light appears to come from a definite direction and creates distinct soft edged shadows.

5 Available or Existing Light - Outdoors
Evaluate the lighting situation and how it affects the subject. You can’t change light outdoors, you can work with it. Direct light can produce prominent and pleasing shadows. Diffused light, such as in shade, is soft and revealing.

6 Available or Existing Light - Indoors
Can be contrasty or flat, depending on the source of light. Expose for the most important parts of the picture. The light is often relatively dim, be prepared.

7 Artificial Light The same properties are present in artificial light as in available light. Directionality of lighting. Lighting Contrasts. Hard light: Light that is directional and not diffused. Soft light: Light that is diffused and without clear direction. Use the type of light and its distance to control the light on your subject. Three basic functions of the lighting set-up. Modeling. Texturing. Highlights and shadows.

8 Lights and Other Lighting Equipment
Types of Artificial Light Diffusers and Filters Photofloods & Quartz-halogen bulbs are for use with indoor color films. Diffusion screens Tents Softbox Filter holders Supports for Lights and Other Devices Flash equipment is used with daylight-balanced color films. Light stands Cross arm or Boom Umbrella mount Background or seamless paper and support stand Reflectors and Light-Control Devices Bowl-shaped reflectors Snoots Umbrella reflectors Reflector Flats Flags Barn doors/Baffles

9 The Main Light: The Dominant Source
The most natural-looking light imitates light from the sun. Lighting can influence the mood and/or character of an image. Most photographs made with artificial light use more than one light source.

10 The Fill Light: Lightens Shadows
Fill light makes shadows less dark – particularly useful with color transparencies. Artificial lighting often requires fill light. Natural daylight scenes can often benefit from fill light. Reflectors can be effective for adding fill light. Flash can also be used for fill lighting. 1:1 Ratio No difference between the lit side and the shadow side of the subject. 2:1 Ratio The lit side is twice as light as the shadow. (one-stop difference) 4:1 Ratio (two-stop difference) 8:1 Ratio (three-stop difference)

11 Lighting With Flash The most practical artificial light source available. Can be used indoors or outdoors. The light is portable and predictable. The burst of light from electronic flash is very brief. Advantages: Stops motion. Delivers measured and repeatable quantity of light. Disadvantages: Can’t “see” how light affects the subject. Must be synchronized with the camera’s shutter. Studio Flash Units Handle-mount Flash Hot-shoe Flash Built-in Flash

12 Basic Flash Techniques
Simplest method. Move around and shoot quickly. Light tends to be flat. More texture and volume than on camera. Easy to let aim wander. Works best relatively close to subject. Direct Flash On Camera Direct Flash Off Camera Softer and more natural than direct. Flash can be left on the camera. Soft lighting, with good modeling and features. On auto-exposure, the sensor must be pointed toward the subject. Flash Bounced From Above Flash Bounced From Side

13 Flash Exposure Variables
Flash-to-subject distance. Most critical factor in determining exposure. Inverse square law. Flash unit output (Flash Power). Watt-seconds can describe a unit’s power. Beam-Candle-Power-Seconds (BCPS) can describe a unit’s power. The Guide number is the easiest and most commonly used. The higher the guide number the more powerful the flash. Reflector. Orientation: Vertical or Horizontal Adjustable: Wide, Normal or Telephoto. Reflectance and/or ambient light. High or Low. Color. Film speed. Shutter speed. Synchronization Guide Number Flash to Subject Distance = f /number Flash Manuals

14 Flash Metering Three basic types of flash units. Manual flash.
Exposure is controlled by the photographer. Exposure can be determined by a flash meter. Exposure can be calculated based on the film speed and power of the unit. Exposure commonly found by using a flash unit’s calculator dial. Automatic flash. Determines duration of flash by measuring light reflected back from the subject during the exposure. Has light-sensitive cell. Has electronic thyristor circuitry. Some units can also be operated manually. Dedicated flash. Units are matched to a specific camera. Do not use with other cameras. Can utilize through-the-lens metering or automatic functions.

15 Flash Exposures: Using a Flash Unit’s Calculator Dial
An automatic flash can control exposure with a sensor on the flash unit. Set the camera’s shutter to a speed that will synchronize with the flash. Actual Flash Calculator Vivitar 285HV Flash “Generic” Flash Calculator

16 Fill Flash: To Lighten Shadows
Shadows can be very dark in a sunlit scene. Flash used as an addition to the basic exposure can open up dark shadows so they show detail. Without flash, a photographer can get a good exposure for the brighter part of a scene or for the shaded part, but not for both. Color slide film and digital photographs particularly benefit from using flash for fill light. Exposed for shaded foreground, no flash. Exposed for sunlit background, no flash. Exposed for sunlit background, flash lightens shaded foreground.

17 Flash Plus Available Light
Shaded subject against bright background, no fill. Shaded subject with flash fill 2 stops less than background. Follow steps outlined in your textbook: Page (9th Edition) Page (10th Edition) Shaded subject with flash fill 1 stop less than the background. Shaded subject with flash fill equal to the background.

18 Controlling Background Brightness
You can use flash plus existing light to make the background lighter or darker. Creative use of exposure can be a valuable tool for scientific photography. Bull Thistles, by natural lighting. Strong side lighting and distracting background effects combine to make a visually confusing picture. The same plants, with a flash providing frontal lighting with the exposure balanced so that the natural lighting was two stops underexposed.

19 Flash and Available Light: Additional Considerations
Natural sunlight. Diffused light, such as in shade, can be soft and revealing. However, at the slower shutter speeds that would be needed for greater depth-of-field, camera movement can limit sharpness. The same subject by close-up flash can yield colors that look brighter. The speed of the flash combined with the use of smaller apertures can also produce a greater depth-of-field. Electronic flash

20 Lighting Textured Objects
Lighting for a textured object depends on whether you want to emphasize texture. Shadows must be seen if the texture is to be prominent. Front lighting minimizes texture. Side lighting emphasizes texture

21 Lighting Reflective Objects
Photographing objects with glossy surfaces can be like photographing a mirror. Reflections can be controlled in various ways. Polarizing filters if object is non-metallic. Tenting an object (shown below).

22 Lighting Translucent Objects
Generally presents the same problems as lighting reflective objects. Can be from behind or by bouncing light off the background. Use a seamless background if possible

23 Lighting and Photographing Aquariums and Glass Display Cases
Flash off camera, and on the acute side of the lens-axis/glass angle results in a reflection that is directed away from the lens – light loss is about one stop. Flash on camera usually results in a reflection that obscures the subject.

24 Good photographers often break as many rules as they observe.
Follow your text and try to understand the logic behind the techniques, but don’t be afraid to take a chance now and then and do things differently.

25 Use your references: Photography 9th. Ed., London, Upton, Stone, Kobré, Brill, Prentice Hall, Upper Saddle River, NJ, 2005 Chapter 13 / Lighting Pages 227 – 258 (9th Edition) - Pages 221 – 253 (10th Edition) Appendix: Troubleshooting (Pages (9th Edition) *Pg. 397 (Pages (10th Edition) *Pg. 389

26

27 Flash unit checked out to Marine Technology students.

28 Guide Number 15/49 Speedlight (ISO 200, m/ft; Guide Number at ISO 100 is 11/36).

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31 Flash Problems One side of the film is dark. Unwanted reflections.
Too fast a shutter speed with a camera that has a focal-plane shutter. Synchronize the shutter with the flash – 1/60 sec. is safe. One side of the film is dark. When photographing scenes that include reflective surfaces, move the camera and/or flash to one side so that you shoot or illuminate the scene at an angle to the reflecting surface. Unwanted reflections.

32 Flash Problems Unwanted shadows.
Move the subject away from a wall so shadows fall on the ground and out of the film frame. Sighting along a line from the flash to the subject will help predict how the shadows will be cast. Unwanted shadows. Parts of the original scene are at different distances from the flash. Try to group important parts of the subject at about the same distance from the flash. Part of scene exposed correctly, part too light or too dark.

33 Flash Problems Moving subject partially blurred – “ghosting”.
Most likely to occur when existing light is bright and the camera’s shutter speed is relatively slow. Make sure your shutter is set to the fastest speed usable with the flash. You may also be able to dim the existing light, shoot when the subject isn’t moving so much, or shoot with the existing light alone. Consider deliberately combining the sharpness and blur. Moving subject partially blurred – “ghosting”. Light reflecting from the blood-rich retina inside the eye. Have the person look away from the camera or move the flash away from the camera. Some flash units have a red-eye reduction mode: the flash lights up briefly before the main exposure so that the subject’s iris contracts, reducing the amount of visible red. Red appearance to a person’s or an animals eyes – “red eye”.

34 Subject appears too dark or too light.
Flash Problems Subject appears too dark or too light. If the subject appears too light, the scene was overexposed. In manual operation, close down the aperture about a stop when shooting in small, light-colored rooms to compensate for excess light bouncing back from walls and ceiling. If your flash pictures are usually overexposed, try setting the flash unit’s film-speed dial to twice the speed you are using. If the subject appears too dark, the scene was underexposed. In manual operation, increase the exposure about a stop for scenes shot outdoors at night or in a large room like a gym. If your flash pictures are frequently too dark, try setting the flash unit’s film-speed dial to half the speed you are using.


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