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التصوير الفوتوغرافي الملون .. المرشد خطوة بخطوة للتصوير الفوتوغرافي
COLOR PHOTOGRAPHY
STEP 1 : Color film
STEP 2 : Color picture building
If you want to work in color this section of the book is essential . It introduces all the special technical and visual aspects of camera technique in color . It also gives you necessary background information for the next section which deals with color processing and printing . You should read through the Steps in this section in order , because each builds on the one before , introducing and explaining terms as you go along .
Some people start their photography with color . This book introduced black and white photography first , because it is simpler and cheaper . All the basic camera and picture building techniques have been presented in black and white . You should therefore have worked through these earlier sections at least before beginning color photography .
Color photography introduces several new factors . You must consider the color of lighting as well as its direction and quality , and use film designed to match the type of light source - daylight , flash , or studio lamps . You have to decide whether to work with color slides , or color negatives and prints . And you must take rather more care over setting exposure ; because errors here can upset color rendering as well as density and contrast .
Most important of all , you now need to think and see in terms of color , building a further visual vocabulary on to the black and white aspects you have already covered . The later pages of this section therefore discuss using color schemes and juxtaposition- ing colors to achieve particular effects . This color vocabulary is essentially a practical guide , so you should explore the topics discussed by finding appropriate subjects and situations , and taking pictures as you go along .
You can see results most directly if you use slide film , because this eliminates the changes that can occur in printing . You can immediately trace the effects of different amounts of exposure , or types of lighting . It is also cheaper per picture . If you intend eventually to do color darkroom work , you may prefer to use color negative film ( and have it commercially processed and printed ) so that you will have plenty of negatives to work from .
Arrangement of steps
The first Step in this section discusses different types of color film . You will see here how color film really consists of three black and white layers , coated one on top of the other . This relates directly to the " balancing " of color films to give accurate colors with particular types of light source . If you use the wrong lighting , you will have to use a correcting filter over your lens .
Step two begins by introducing the key terms used when discussing color , and the inter - relationships of various colors of the spectrum . ( This Step is also essential reading before tackling color printing . ) The pages on picture building in color , show you how to use color contrast , color harmony , and muted or strident colors , to produce particular effects . Don't be put off by the number of factors to consider . As in the black and white picture building section , the illustrations are chosen deliberately to emphasize the aspect being discussed and exclude others . But in practice , you will find that the color relationships in scenes overlap several definitions .
Color itself can form the main , dominant element in your picture , particularly if you manipulate it by means of filters , or choice of film and lighting . Pete Turner's pictures on pages 186-7 are examples of this approach . More often you will use color along with the other picture - building elements to strengthen your main subject . You can see this in the work of Rolph Gobits ( see p . 179 ) and Gerry Cranham ( see pp . 190-1 ) .
What is color ?
Before the seventeenth century it was believed that color existed in objects , irrespective of the light by which they were seen . Isaac Newton proved that light itself is the real source of all colors . He split sunlight into a color spectrum by passing it at a certain angle through a glass prism . He then directed the band of colors through a second prism , which re - combined them into a beam of colorless light . Clearly , the colors formed did not exist in the actual glass , but came from the light itself .
A green leaf looks green because it reflects the green wavelengths present in white light . You can see this yourself by examining a green object under a red safelight - because the lighting contains no green , the object appears black . To take a more familiar example : when you buy a colored garment in a store , you often take it to a door or window to check how it looks in daylight . This is because you know that incandescent interior lighting , although " white " , contains a slightly different mixture of wavelengths from white light outside , and so alters the apparent color of the garment .
Light is the source of all color . Colored objects are reflecting light selectively . They reflect only the wavelengths ( i.e. colors ) that you see , and absorb the rest . There are four different ways this can happen : selective reflection by pigment molecules ; scattering : diffraction ; and interference .
Pigment is the most common selective reflector of light . Molecules of pigment are present in practically every object created by nature and man - ranging from plants and animals to dyes and paints . Each pigment has a " resonance " or affinity for a particular wavelength or group of wavelengths . The pigment molecules most readily absorb these colors . A red flower , for instance , contains pigment molecules which " resonate " with . and absorb all the wavelengths in " white " light other than red . So that red is the only color it reflects .
Some colors are formed by a special kind of reflection - scattering . The most obvious example is a blue sky : it contains gases which tend to scatter the short ( blue ) wavelengths of sunlight . If the earth carried no atmosphere , the sun would appear in a black sky , just as it does in color pictures taken on the moon . Our sky often contains dust and moisture molecules too . which scatter a wider range of wavelengths and make the blue appear paler . Since dust and pollution are cleansed from the atmosphere by rain , skies are usually a deeper blue in color when strong sunshine follows a shower .
Scattering of light produces a wide range of sky colors . At sunrise and sunset , light from the low sun travels obliquely through the atmosphere along a path hundreds of miles longer than at midday . Consequently , nearly all the blue wavelengths are scattered on the way ; so the sunlight that reaches you is orange , or even red ( see p . 154 ) .
A few surfaces appear colored because they cause diffraction or interference . Diffraction of light occurs when light strikes a surface structured with extremely fine lines or ridges . These break up the light in such a way that some wavelengths are suppressed and others strengthened . The result is a shimmer of muted hues according to the angle from which you view . You can see diffraction colors on records , shot silk fabrics , and mother - of - pearl .
Interference colors occur on soap bubbles , or splashes of oil on water . Both soap and oil form extremely thin membranes . Light is reflected from both the front and back surfaces of the membrane , so that the waves are slightly " out of phase " , reinforcing some wavelengths and suppressing others . This produces changing colors across the surface .
Discovering the spectrum
A contemporary copper engraving by B. Rode , left , shows Newton in a darkened room , using two prisms to separate a beam of light into the colors of the spectrum , and then reconstitute it . This crucial experi- ment , in 1666 , demonstrated that light is the source of all colors .
Color vision and color film
Things around you derive their colors from the interactions of light source and subject surface . But the way they look colored also involves the response of the actual receiver - your eyes ( or photographic color film , eventually viewed by your eyes) .
As you read on pages 20-1 , human vision depends partly on the eye and partly on the brain's response to images .
Isaac Newton
The portrait of Newton . left . was painted in 1702 by Godfrey Kneller . shortly before the publication of his major work on the behavior of light . which included his color theory .
Title page of Newton's " Optics "
Newton published his discovery of the spectrum and his color theory in his major work . " Optics " . The title page of the original Latin edition . published in London in 1707. is shown left . The work also covered the laws of reflection and refraction of light , and laid the foundations of optics as a science .
The back surface of your eye is covered by a retina - a microscopic net of about 130 million light - sensitive cells . Some cells respond to color ; these are known as cones . They are grouped mostly near the center of the retina . Other more numerous cells , known as rods , are much more sensitive to light , but cannot identify colors . They are mostly located away from the retina center . Cone cells respond to light as if they were an even mixture of three different kinds of receptor - each sensitive either only to red wavelengths . or only to green , or only to blue . So each color in the image formed within the eye gives rise to a different combination of the three basic signals . Blue will affect only one type of receptor ; greenish - blue will affect two receptors ; white or gray will affect all three . This tri - color concept is also used as the basis of color film : which consists of three separate emulsion layers , sensitive to red , green , and blue light .
Unlike color film however , the eye alters its sensitivity away from color and toward black and white in dim light . The color of a car is almost impossible to see by moonlight because at night you see almost entirely by the highly sensitive , but color - blind rods . Color film does not change in dim light . You can take color pictures by moonlight , although your results will then be distorted by reciprocity failure ( see p . 107 ) .
Another difference between color from the central grouping of cones on the retina . Your eyes only respond fully to color in a narrow central zone of your field of view the zone where you resolve greatest detail , and where you are focusing these words as you read . It is only because your eyeball moves almost continuously , to place whatever you are concentrating on within this retina zone , that you do not notice this . Try staring fixedly ahead , then bring a colored object at arm's length just within your field of view . You are conscious of its movement and general shape ; but there are insufficient cones in this peripheral zone to make you sure of the object's color -until you turn your eye .
Provided they look squarely at objects , in strong light , most people can differentiate between the various hues ( colors ) , and distinguish their saturation ( richness ) , and brightness ( dark or light color ) . About 8 % of men and 0.5 % of women do however suffer cone or nerve deficiencies which produce some form of color blindness . The most common type leaves you unable to differentiate clearly between greenish and reddish colors , and gray . Defective color vision is obviously a handicap in color photography , and you will find that it makes doing your own color printing impossible . So have your eyes checked by an optician if you are in any doubt .
The eye provides your brain with signals denoting the color of objects , which the brain then interprets . It has a color memory and this means that often you tend to " see " the colors you expect . You " know " from experience that grass is green and lips are red . so even when looking through tinted spectacles or viewing in colored light you are not muddled . You will , however , become confused as soon as you see an unfamiliar object - suddenly the colored light or glasses will become an obstruction to understanding what you see . You can accept the paper on this page as white , when reading outdoors in bluish daylight . If you then walk into a room lit by incandescent lamps . you will be briefly conscious of the more orange light but soon accept the page again as white . Colors inside the room will appear correct , provided you cannot compare them directly with the same objects lit by daylight . In other words , your color vision is capable of adaption to different conditions .
Color film cannot adapt . Film designed for daylight gives an orange cast to pictures if used in artificial light . Even the adaption of your eye finds this cast unacceptable , particularly when the color photograph is viewed in an environment lit by daylight . Color film is therefore more objective than the eye : it records what is present rather than what it wants to see . But you can also use it subjectively - for example by over- or underexposing to change color saturation ( see p . 153 ) .
Color relationships
When you change from black and white to color photography , the biggest difference is learning to observe and use subtle color relationships in your subjects - aspects which up to now you could ignore . Some colors are " cold " and others " warm " , some are dynamic , others quiet ; certain colors have a harmonious relationship , whereas others such as orange and purple always give a strident , shock effect . Color reactions of this type can greatly strengthen your color photographs , if handled well .
Gray looks lighter when seen against black , and darker against white . Adjacent colors create such effects too . The same gray looks redder against a green background , and greener against red . You can take advantage of " simultaneous contrast " effects like these to put boldness into a composition , when in black and white it would look weak and flat .
Color provides an expansion of your photographic range , but it also requires new skills . Until you can manage color relationships clearly , you must take care that color does not distract or confuse the eye , or unbalance your composition . Strong colors will be particularly dominating to the exclusion of other elements , perhaps even the subject itself . But once you are really used to the new materials , you will find color photography a medium with great potential .
COLOR PHOTOGRAPHY
STEP 1 : Color film
STEP 2 : Color picture building
If you want to work in color this section of the book is essential . It introduces all the special technical and visual aspects of camera technique in color . It also gives you necessary background information for the next section which deals with color processing and printing . You should read through the Steps in this section in order , because each builds on the one before , introducing and explaining terms as you go along .
Some people start their photography with color . This book introduced black and white photography first , because it is simpler and cheaper . All the basic camera and picture building techniques have been presented in black and white . You should therefore have worked through these earlier sections at least before beginning color photography .
Color photography introduces several new factors . You must consider the color of lighting as well as its direction and quality , and use film designed to match the type of light source - daylight , flash , or studio lamps . You have to decide whether to work with color slides , or color negatives and prints . And you must take rather more care over setting exposure ; because errors here can upset color rendering as well as density and contrast .
Most important of all , you now need to think and see in terms of color , building a further visual vocabulary on to the black and white aspects you have already covered . The later pages of this section therefore discuss using color schemes and juxtaposition- ing colors to achieve particular effects . This color vocabulary is essentially a practical guide , so you should explore the topics discussed by finding appropriate subjects and situations , and taking pictures as you go along .
You can see results most directly if you use slide film , because this eliminates the changes that can occur in printing . You can immediately trace the effects of different amounts of exposure , or types of lighting . It is also cheaper per picture . If you intend eventually to do color darkroom work , you may prefer to use color negative film ( and have it commercially processed and printed ) so that you will have plenty of negatives to work from .
Arrangement of steps
The first Step in this section discusses different types of color film . You will see here how color film really consists of three black and white layers , coated one on top of the other . This relates directly to the " balancing " of color films to give accurate colors with particular types of light source . If you use the wrong lighting , you will have to use a correcting filter over your lens .
Step two begins by introducing the key terms used when discussing color , and the inter - relationships of various colors of the spectrum . ( This Step is also essential reading before tackling color printing . ) The pages on picture building in color , show you how to use color contrast , color harmony , and muted or strident colors , to produce particular effects . Don't be put off by the number of factors to consider . As in the black and white picture building section , the illustrations are chosen deliberately to emphasize the aspect being discussed and exclude others . But in practice , you will find that the color relationships in scenes overlap several definitions .
Color itself can form the main , dominant element in your picture , particularly if you manipulate it by means of filters , or choice of film and lighting . Pete Turner's pictures on pages 186-7 are examples of this approach . More often you will use color along with the other picture - building elements to strengthen your main subject . You can see this in the work of Rolph Gobits ( see p . 179 ) and Gerry Cranham ( see pp . 190-1 ) .
What is color ?
Before the seventeenth century it was believed that color existed in objects , irrespective of the light by which they were seen . Isaac Newton proved that light itself is the real source of all colors . He split sunlight into a color spectrum by passing it at a certain angle through a glass prism . He then directed the band of colors through a second prism , which re - combined them into a beam of colorless light . Clearly , the colors formed did not exist in the actual glass , but came from the light itself .
A green leaf looks green because it reflects the green wavelengths present in white light . You can see this yourself by examining a green object under a red safelight - because the lighting contains no green , the object appears black . To take a more familiar example : when you buy a colored garment in a store , you often take it to a door or window to check how it looks in daylight . This is because you know that incandescent interior lighting , although " white " , contains a slightly different mixture of wavelengths from white light outside , and so alters the apparent color of the garment .
Light is the source of all color . Colored objects are reflecting light selectively . They reflect only the wavelengths ( i.e. colors ) that you see , and absorb the rest . There are four different ways this can happen : selective reflection by pigment molecules ; scattering : diffraction ; and interference .
Pigment is the most common selective reflector of light . Molecules of pigment are present in practically every object created by nature and man - ranging from plants and animals to dyes and paints . Each pigment has a " resonance " or affinity for a particular wavelength or group of wavelengths . The pigment molecules most readily absorb these colors . A red flower , for instance , contains pigment molecules which " resonate " with . and absorb all the wavelengths in " white " light other than red . So that red is the only color it reflects .
Some colors are formed by a special kind of reflection - scattering . The most obvious example is a blue sky : it contains gases which tend to scatter the short ( blue ) wavelengths of sunlight . If the earth carried no atmosphere , the sun would appear in a black sky , just as it does in color pictures taken on the moon . Our sky often contains dust and moisture molecules too . which scatter a wider range of wavelengths and make the blue appear paler . Since dust and pollution are cleansed from the atmosphere by rain , skies are usually a deeper blue in color when strong sunshine follows a shower .
Scattering of light produces a wide range of sky colors . At sunrise and sunset , light from the low sun travels obliquely through the atmosphere along a path hundreds of miles longer than at midday . Consequently , nearly all the blue wavelengths are scattered on the way ; so the sunlight that reaches you is orange , or even red ( see p . 154 ) .
A few surfaces appear colored because they cause diffraction or interference . Diffraction of light occurs when light strikes a surface structured with extremely fine lines or ridges . These break up the light in such a way that some wavelengths are suppressed and others strengthened . The result is a shimmer of muted hues according to the angle from which you view . You can see diffraction colors on records , shot silk fabrics , and mother - of - pearl .
Interference colors occur on soap bubbles , or splashes of oil on water . Both soap and oil form extremely thin membranes . Light is reflected from both the front and back surfaces of the membrane , so that the waves are slightly " out of phase " , reinforcing some wavelengths and suppressing others . This produces changing colors across the surface .
Discovering the spectrum
A contemporary copper engraving by B. Rode , left , shows Newton in a darkened room , using two prisms to separate a beam of light into the colors of the spectrum , and then reconstitute it . This crucial experi- ment , in 1666 , demonstrated that light is the source of all colors .
Color vision and color film
Things around you derive their colors from the interactions of light source and subject surface . But the way they look colored also involves the response of the actual receiver - your eyes ( or photographic color film , eventually viewed by your eyes) .
As you read on pages 20-1 , human vision depends partly on the eye and partly on the brain's response to images .
Isaac Newton
The portrait of Newton . left . was painted in 1702 by Godfrey Kneller . shortly before the publication of his major work on the behavior of light . which included his color theory .
Title page of Newton's " Optics "
Newton published his discovery of the spectrum and his color theory in his major work . " Optics " . The title page of the original Latin edition . published in London in 1707. is shown left . The work also covered the laws of reflection and refraction of light , and laid the foundations of optics as a science .
The back surface of your eye is covered by a retina - a microscopic net of about 130 million light - sensitive cells . Some cells respond to color ; these are known as cones . They are grouped mostly near the center of the retina . Other more numerous cells , known as rods , are much more sensitive to light , but cannot identify colors . They are mostly located away from the retina center . Cone cells respond to light as if they were an even mixture of three different kinds of receptor - each sensitive either only to red wavelengths . or only to green , or only to blue . So each color in the image formed within the eye gives rise to a different combination of the three basic signals . Blue will affect only one type of receptor ; greenish - blue will affect two receptors ; white or gray will affect all three . This tri - color concept is also used as the basis of color film : which consists of three separate emulsion layers , sensitive to red , green , and blue light .
Unlike color film however , the eye alters its sensitivity away from color and toward black and white in dim light . The color of a car is almost impossible to see by moonlight because at night you see almost entirely by the highly sensitive , but color - blind rods . Color film does not change in dim light . You can take color pictures by moonlight , although your results will then be distorted by reciprocity failure ( see p . 107 ) .
Another difference between color from the central grouping of cones on the retina . Your eyes only respond fully to color in a narrow central zone of your field of view the zone where you resolve greatest detail , and where you are focusing these words as you read . It is only because your eyeball moves almost continuously , to place whatever you are concentrating on within this retina zone , that you do not notice this . Try staring fixedly ahead , then bring a colored object at arm's length just within your field of view . You are conscious of its movement and general shape ; but there are insufficient cones in this peripheral zone to make you sure of the object's color -until you turn your eye .
Provided they look squarely at objects , in strong light , most people can differentiate between the various hues ( colors ) , and distinguish their saturation ( richness ) , and brightness ( dark or light color ) . About 8 % of men and 0.5 % of women do however suffer cone or nerve deficiencies which produce some form of color blindness . The most common type leaves you unable to differentiate clearly between greenish and reddish colors , and gray . Defective color vision is obviously a handicap in color photography , and you will find that it makes doing your own color printing impossible . So have your eyes checked by an optician if you are in any doubt .
The eye provides your brain with signals denoting the color of objects , which the brain then interprets . It has a color memory and this means that often you tend to " see " the colors you expect . You " know " from experience that grass is green and lips are red . so even when looking through tinted spectacles or viewing in colored light you are not muddled . You will , however , become confused as soon as you see an unfamiliar object - suddenly the colored light or glasses will become an obstruction to understanding what you see . You can accept the paper on this page as white , when reading outdoors in bluish daylight . If you then walk into a room lit by incandescent lamps . you will be briefly conscious of the more orange light but soon accept the page again as white . Colors inside the room will appear correct , provided you cannot compare them directly with the same objects lit by daylight . In other words , your color vision is capable of adaption to different conditions .
Color film cannot adapt . Film designed for daylight gives an orange cast to pictures if used in artificial light . Even the adaption of your eye finds this cast unacceptable , particularly when the color photograph is viewed in an environment lit by daylight . Color film is therefore more objective than the eye : it records what is present rather than what it wants to see . But you can also use it subjectively - for example by over- or underexposing to change color saturation ( see p . 153 ) .
Color relationships
When you change from black and white to color photography , the biggest difference is learning to observe and use subtle color relationships in your subjects - aspects which up to now you could ignore . Some colors are " cold " and others " warm " , some are dynamic , others quiet ; certain colors have a harmonious relationship , whereas others such as orange and purple always give a strident , shock effect . Color reactions of this type can greatly strengthen your color photographs , if handled well .
Gray looks lighter when seen against black , and darker against white . Adjacent colors create such effects too . The same gray looks redder against a green background , and greener against red . You can take advantage of " simultaneous contrast " effects like these to put boldness into a composition , when in black and white it would look weak and flat .
Color provides an expansion of your photographic range , but it also requires new skills . Until you can manage color relationships clearly , you must take care that color does not distract or confuse the eye , or unbalance your composition . Strong colors will be particularly dominating to the exclusion of other elements , perhaps even the subject itself . But once you are really used to the new materials , you will find color photography a medium with great potential .
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