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Color Photography

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MSC 258
Multimedia Presentations
Color Photography
With Excerpts and examples from:
Color Photography: A Working Manual
Henry Horenstein, Little, Brown & Company, USA, 1995
Photography
8th. Ed., London, Upton, Stone, KobrГ©, Brill, Prentice Hall,
Upper Saddle River, NJ, 2005
Photographing in Color
More than 95 percent of all photographs
taken are in color.
пЃ® Not that long ago, color photography was
looked upon with skepticism by many
creative and professional photographers.
пЃ® Whatever materials and processes are used,
it’s still the individual who creates the final
result.
пЃ®
Shooting color film is in most ways
similar to shooting black-and-white film.
Load the camera.
пЃ® Adjust the film speed.
пЃ® Set the lens aperture, shutter speed and
focus. (or let the camera do any of these things for you)
пЃ® Naturally, you also have to consider the
content, composition, and subject lighting.
пЃ® Press the shutter button to make the
exposure.
пЃ®
Color: Additive or Subtractive
пЃ®
All colors can be created by mixing three
primary colors.
– Additive primaries (red, green, and blue)
B
R
G
– used in television sets and computer monitors.
пЃ® The additive process mixes red, green, & blue light in
varying proportions to produce any color.
пЃ® Mixed together at full strength, all three primaries
produce white light.
пЃ® Additive mixing requires three separate light sources.
пЃ® RGB
Color: Additive or Subtractive
пЃ®
All colors can be created by mixing three primary
colors.
– Subtractive primaries (cyan, magenta, and yellow)
CMYK – used in all modern color films, as well as in
printing.
пЃ® These colors absorb red, green, and blue wavelengths, thus
subtracting them from white light.
пЃ® The subtractive primaries are the complementary colors to
the three additive primaries.
пЃ® Mixed all together at full strength, the subtractive primaries
absorb all colors of light, producing black (“K”).
пЃ® Mixed in varying proportions, they can produce any color
in the spectrum.
пЃ®
B
R
G
Color Photographs: Three Image Layers
пЃ®
A color photograph begins as three superimposed
black-and-white negatives.
пЃ®
пЃ®
пЃ®
Color film consists of three layers of emulsion, with each layer
basically the same as in B & W film, but responding to different
parts of the spectrum.
– The top layer is only sensitive to blue light.
– The middle layer records the green light.
– The bottom layer is exposed only by red light.
Colors are created during development.
– The developer converts the light-sensitive silver halides in the
layers to metallic silver.
– As it does so, the developer oxidizes and combines with dye
couplers that are either built into the layers of emulsion or
added during development
A color transparency, for example, has three layers of dye images
superimposed on a transparent support.
Choosing A Color Film
пЃ®
Different types and/or brands of color film vary
in their color rendition, sharpness, contrast,
graininess, and other characteristics.
– Negative films, also called “print films”.
В» Produce an image that is opposite in colors and density of
the original scene.
пЃ®
пЃ®
Designed to be printed to create a positive image, usually on
paper but occasionally on a clear film base for overheads, etc.
Color negatives contain an overall orange “mask” which is
formed during processing to help control color balance and
contrast in printing.
» Usually identified by the suffix – color attached to the
manufacturer’s name.
пЃ®
Agfacolor, Ektacolor, Fujicolor, Kodacolor, etc.
Choosing A Color Film
– Reversal films, also called “transparency film”.
В» The film exposed in the camera is processed so that the
negative image is reversed to make a positive transparency
with the same colors and density as the scene.
пЃ®
пЃ®
Designed to be projected or viewed directly and can also be printed
or scanned.
35mm transparency films also are called “slide films”.
– A slide is a transparency framed in cardboard or plastic mount.
» Generally identified by the suffix – chrome attached to the
manufacturer’s name.
пЃ®
Agfachrome, Ektachrome, Fujichrome, Kodachrome, etc.
Choosing A Color Film
пЃ®
Professional films are designed for professional
photographers, who often have exacting standards, especially for
color balance.
– Professional films are shipped to the camera store when they are at their
peak in terms of:
В» Color balance
В» Speed
В» Contrast
– Professional films have a shorter expiration date and should be used
immediately and/or kept refrigerated.
– Other characteristics of professional films may include:
В» A heavier film base and a more durable emulsion.
В» More flexibility in push and pull processing.
– Generally more expensive than comparable amateur films.
Choosing A Color Film
пЃ®
Consumer oriented films are typically designed and
manufactured to different color specifications.
– Amateur films are shipped before they reach their peak so they will
reach their optimum color balance some time after they reach the
retailer.
– Amateur films have a longer expiration date and can be stored at
room-temperature.*
– An amateur version of a certain film may have more highly
saturated color and higher contrast for added impact.
В» The professional version of the same film may have less intense
color & lower contrast for more accurate skin tones & greater
subject detail.
– Nonprofessionals are more likely to accept some variation in color
balance from one roll of film to the next.
* Although they are not expected to be refrigerated, they too keep better when kept cool.
Film Characteristics
пЃ®
Different types of color film vary in their color rendition,
sharpness, contrast, graininess, and other characteristics.
– Color quality varies widely from film to film.
» Some films have a warm bias – others don’t.
В» Some films produce more saturated (intense) colors than others.
В» Dyes used by different manufacturers vary.
– Film speed (ISO)has an important effect on how film renders a
subject.
В» Slower films generally produce:
пЃ®
пЃ®
пЃ®
пЃ®
пЃ®
Greater sharpness.
Richer Colors
Often more contrast.
A less grainy appearance.
Higher resolution.
В» Practical considerations always come into play.
Exposing Color Films
пЃ®
Correct film exposure is the primary factor in determining
whether or not you will get good negatives and
transparencies.
– For the most part, techniques for exposing B & W films also apply
to exposing color films.
– It’s easier to get good exposures (prints) with negative films than
with transparency films.
В» Negative films have more exposure latitude (margin for error).
В» Transparency films tolerate very little under or overexposure (1/2 to
2/3 stop).
В» Unlike negatives, transparencies become lighter with more exposure
and darker with less.
– There’s more margin for error (latitude) when the lighting is soft
(low contrast) than when it’s hard (high contrast).
Exposure Latitude:
How Much Can Exposures Vary?
Corrected Print
-4 stops -3 stops
Corrected Print
-2 stops
-1 stop
+1 stop
Color Negatives – Uncorrected Contact Sheet
-4 stops
-3 stops
-2 stops
-1 stop
+2 stops
+3 stops
+4 stops
+3 stops
+4 stops
Transparencies
+1 stop
+2 stops
Color films and lighting must be balanced
for neutral color.
пЃ®
пЃ®
пЃ®
пЃ®
пЃ®
Color film records slight shifts in color balance
that result from different types of light bulbs or
color shifts in daylight.
Unlike black & white films, color films allow
relatively little contrast control.
Subject lighting is a critical factor in determining
color balance and contrast.
The balance of colors in light is measured as color
temperature on the Kelvin scale.
Different color films are made for different color
temperatures.
Color Balance: Color Temperature
Cool Colors or “Hues”
+
Daylight: Clear Skylight/No Direct Sun
10,000K
9,000K
Daylight: Dull, Foggy Weather
8,000K
7,000K
Daylight: Overcast Sky
6,000K
Electronic Flash
5500K } Daylight Film
Daylight: Noon, Direct Sun
5,000K
Industrial Smog
4,000K
3,000K
3400K
3200K
Photoflood Bulb
3200K } Tungsten Film
Photoflood Bulb
75 Watt Household Bulb
2,000K
1,000K
Candlelight
Warm Colors or “Hues”
Color Balance and the Light Source
Television
Monitor
Computer
Monitor
Blue Neon
Sunset
Open Shade Outdoors
Midday Sunlight
Fluorescent
Tube
Tungsten
Bulb
Candlelight
Daylight Color Film, White Background, Gray Shirt
Filters for Black & White Film
пЃ®
With black-and-white films, colored filters are
used to control the relative lightness and
darkness of tones (contrast).
Actual Scene
In Color
B&W
No Filter
B&W
#8 Yellow
Filter
B&W
#25 Red
Filter
Filters for B & W and Color Films
Skylight or Ultraviolet
пЃ® Neutral Density
пЃ® Polarizing
пЃ®
– Darkens Blue Sky
– Reduces Reflections
Without Polarizing Filter
With Polarizing Filter
Filters to Balance Color
пЃ®
Filters can correct the color balance.
– Daylight film – Tungsten light.
– Tungsten film – Daylight
– Daylight film – Fluorescent light
пЃ®
пЃ®
Very long exposures can change color balance.
Color balance is more important when making color
slides than it is with color negatives.
Filters to Balance Color
Filter
85B
Tungsten Film in Daylight
Tungsten Film in Natural Daylight
with 85B Filter
Daylight Film in Natural Daylight
Filter
80A
Daylight Film in Tungsten Light
Daylight Film in Tungsten Light
with 80A Filter
Tungsten Film in Tungsten Light
Daylight Film in
Fluorescent Light
Filter
FL
Daylight Film in
Fluorescent Light
With FL Filter
Natural light won’t always provide the
color and contrast you want.
пЃ®
Varies enormously depending on factors
such as:
В» Weather (and other atmospheric conditions)
В» Time of day
В» Location
В» Season
Time of day affects color: Specifics may vary
with other factors, but typically changes as shown.
6:30 A.M.
Light is very cool before dawn.
3:45 P.M.
And stays neutral through the
early afternoon.
7:00 A.M.
Light warms as the sun rises.
6:00 P.M.
As the sun goes down, the resulting
light warms up again …
Noon
Light becomes neutral later
in the morning …
8:30 P.M.
Then cools down after sunset.
Season affects color: From season to season color
may change (leaves in the fall or snow in the winter), as does the
color temperature of outdoor light.
Winter
Spring
Summer
Fall
You can only achieve maximum control
over color and contrast by lighting the
subject exactly the way you want to – in a
studio or totally dark room.
Obviously this is not always practical
or possible for photographers or
marine technicians –
Be Aware of the Problems!
Use your references:
Photography
9th. Ed., London, Stone, Upton
пЃ® Prentice Hall,
Upper Saddle River, NJ, 2005
пЃ®
– Chapter 7 / Color
» Pages 138 – 149
В» http://www.prenhall.com/london
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