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DAYLIGHT OR TUNGSTEN ?
way One of the eye's remarkable qualities , not shared by photographic film , is the in which it can accommodate different types of lighting . The colour of daylight varies with the weather and the time of day , and is in all cases very different from that of domestic lighting . Yet , we rarely notice the differences . Film is more rigid in its recording of colour , and in order for scenes to appear normal in a photograph , it is often necessary to use filters or to choose a type of film that is balanced for the particular light source .
Most colour films are , naturally enough , balanced for daylight . This is , after all , the light under which most photographs are taken . What this means is that a scene photographed on a sunny day will appear to be lit neutrally : whites will photograph white , greys remain pure , without a trace of colour , and flesh tones appear natural . Daylight - balanced films are the standard , and are made to record noon sunlight ( 5500K on the colour temperature scale on page 36 ) as white .
There is , however , another type of film , balanced for tungsten lamps which have a colour temperature of 3200K . This is much more orange than sunlight , as you can check for yourself by shooting an indoor , tungsten - lit scene with regular daylight film . Nearly all tungsten - balanced films are known as Type B. Type A , which is balanced for slightly less orange 3400K lamps , is now almost obsolete ; a Type A Kodachrome is available in some countries .
LEFT This picture was taken on daylight film ; the mixture of natural and tungsten light has given a slight orange cast to the meat . But it is precisely the richness and warmth of colour which gives the image its point , so why filter ?
The reason for the existence of tungsten - balanced films is not candid indoor photography , but the fact that in the past all studio photography was done with incandescent lamps . Being brighter ( hotter ) than ordinary domestic tungsten lamps , these burn whiter . Nowadays , although incandescent photographic lamps are still used , electronic flash is the most popular photographic light source , and this is balanced to the colour of daylight .
Under most circumstances , therefore , daylight - balanced film is the natural choice . Type B film , however , is still remarkably useful . Apart from matching photographic lamps , it partially corrects the very orange cast from domestic tungsten lamps . If the effect that you are looking for does not really need to be perfectly neutral , Type B film may well be sufficient alone , without further filtering .
Another use for Type B film is for long exposures . The reason lies in ' reci- procity failure ' , which is described on page 33. Low light , or the need for very small apertures to give good depth of field , makes longer exposure times necessary . At slow shutter speeds , typically 1 / 10sec and longer , films behave as if they were slower ( less sensitive ) , and colour films acquire a colour cast ( this colour distortion varies according to the make of film ) . Because Type B film is specifically designed for work in the studio where a tripod is normally used , its optimum exposure is much slower than that of daylight film . Even in daylight therefore , Type B film with an appropriate orange filter ( 85B ) will actually give truer colours in a long exposure .
BELOW Two photos that show perfectly the problems and solutions encountered when working with tungsten lighting . One ( RIGHT ) shows the strong orange tint that results from shooting on daylight film a scene that is predominantly lit by tungsten ( the household lamps in the background ) . The other photo ( LEFT ) has a far more natural look , the result of using tungsten - balanced film . An alternative is to use a blue filter .
DAYLIGHT OR TUNGSTEN ?
way One of the eye's remarkable qualities , not shared by photographic film , is the in which it can accommodate different types of lighting . The colour of daylight varies with the weather and the time of day , and is in all cases very different from that of domestic lighting . Yet , we rarely notice the differences . Film is more rigid in its recording of colour , and in order for scenes to appear normal in a photograph , it is often necessary to use filters or to choose a type of film that is balanced for the particular light source .
Most colour films are , naturally enough , balanced for daylight . This is , after all , the light under which most photographs are taken . What this means is that a scene photographed on a sunny day will appear to be lit neutrally : whites will photograph white , greys remain pure , without a trace of colour , and flesh tones appear natural . Daylight - balanced films are the standard , and are made to record noon sunlight ( 5500K on the colour temperature scale on page 36 ) as white .
There is , however , another type of film , balanced for tungsten lamps which have a colour temperature of 3200K . This is much more orange than sunlight , as you can check for yourself by shooting an indoor , tungsten - lit scene with regular daylight film . Nearly all tungsten - balanced films are known as Type B. Type A , which is balanced for slightly less orange 3400K lamps , is now almost obsolete ; a Type A Kodachrome is available in some countries .
LEFT This picture was taken on daylight film ; the mixture of natural and tungsten light has given a slight orange cast to the meat . But it is precisely the richness and warmth of colour which gives the image its point , so why filter ?
The reason for the existence of tungsten - balanced films is not candid indoor photography , but the fact that in the past all studio photography was done with incandescent lamps . Being brighter ( hotter ) than ordinary domestic tungsten lamps , these burn whiter . Nowadays , although incandescent photographic lamps are still used , electronic flash is the most popular photographic light source , and this is balanced to the colour of daylight .
Under most circumstances , therefore , daylight - balanced film is the natural choice . Type B film , however , is still remarkably useful . Apart from matching photographic lamps , it partially corrects the very orange cast from domestic tungsten lamps . If the effect that you are looking for does not really need to be perfectly neutral , Type B film may well be sufficient alone , without further filtering .
Another use for Type B film is for long exposures . The reason lies in ' reci- procity failure ' , which is described on page 33. Low light , or the need for very small apertures to give good depth of field , makes longer exposure times necessary . At slow shutter speeds , typically 1 / 10sec and longer , films behave as if they were slower ( less sensitive ) , and colour films acquire a colour cast ( this colour distortion varies according to the make of film ) . Because Type B film is specifically designed for work in the studio where a tripod is normally used , its optimum exposure is much slower than that of daylight film . Even in daylight therefore , Type B film with an appropriate orange filter ( 85B ) will actually give truer colours in a long exposure .
BELOW Two photos that show perfectly the problems and solutions encountered when working with tungsten lighting . One ( RIGHT ) shows the strong orange tint that results from shooting on daylight film a scene that is predominantly lit by tungsten ( the household lamps in the background ) . The other photo ( LEFT ) has a far more natural look , the result of using tungsten - balanced film . An alternative is to use a blue filter .
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