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THE ZONE SYSTEM
For really fine control over exposure , entire systems have been invented at different times . The most famous of these is the Zone System , used by one of the greatest black - and - white photographers , Ansel Adams . This is certainly a more complicated approach to exposure than is usual , but it does make it possible for the photographer to be in complete control of the tonal values in the image . It takes time , and so is best suited to the photography of static scenes , such as landscapes and architectural subjects .
The Zone System assigns all the levels of brightness in a scene , and all tonal values , to a scale of ten steps . Each of these steps is exactly one stop different from the next , and the scale goes from pure black to pure white . As you can see from the strip ( left ) , Zone 0 is solid black , Zone V in the middle is an average mid - grey , and Zone IX is pure white . By assigning the important tones in the scene to the appropriate zones , it is relatively easy , once you are experi- enced , to see how the contrast range of the subject fits that of the negative and the print .
In many photographic situations , contrast is something of a problem , or at least demands careful attention . A typical scene has a contrast range of about seven stops , and so covers seven zones . A normal black - and - white negative , together with a typical Grade 2 printing paper ( this is the normal grade ) ; can handle this range , but it is important to place the zones correctly .
One of the most important zones is III - textured shadow . This is the value at which dark details can just be seen , and is generally thought of as being a tone that should be preserved in the print . This zone is 2 stops darker than average , and a typical procedure would be to measure it with an exposure meter and then adjust the settings on the camera to 2 stops less than the one indicated .
Comparing the brightness levels in the scene with the 10 - step scale shows which parts , if any , will fall outside the film's brightness range . Treat a medium- speed black - and - white negative film , developed and printed normally , as having a range of seven stops .
The Zones
0 Solid black ; the same as the film rebate ( edges )
I Nearly black ; just recognizably different from Zone 0 .
II The first hint of texture but nothing recognizable III Textured shadow ; the first zone to show recognizable shadow detail .
IV Average shadow value on Caucasian skin , landscape foliage and buildings .
V Middle grey ; 18 % grey test card ; the ' pivot ' value ; light foliage ; dark skin .
VI Caucasian skin ( 36 % reflectance ) ; textured light grey ; shadow on snow .
VII Light skin ; bright areas with texture , such as snow in low sunlight .
VIII Highest zone with any texture .
IX Pure untextured white ; little difference between this and unexposed paper .
ABOVE A typical scene with a contrast range of approximately seven stops . Fortunately , a typical black- and - white negative coupled with normal Grade 2 printing paper can handle this , although it is important to place the zones correctly .
RIGHT Zone III , textured shadow , is one of the most important , since it is the value at which dark details can just be seen . Its dominance in this portrait made it vital that it should be preserved in the finished print .
This sunlit scene covers many brightness values - in other words , it has a high contrast range .
Because we are discussing the tonal reproduction that a photograph offers , the original subject is represented here as an illustration ( 1 ) .
Stage 1 : Using the measuring methods described already , we can make a precise , objective record of the brightness levels in this original scene .
Different exposure meters record their information in different ways . The next picture ( 2 ) shows the scene measured in candles- per - square - foot ( c / ft ) ² , a universal measurement , but not one normally used by photographers , and also in f stops - by assuming a film speed of 100 ASA and a shutter speed of 1/125 sec .
Stage 2 : At this stage the photographer has to decide subjectively what are the important areas of the scene . Because Zone III ( " textured shadow " ) is defined as the darkest shadow area in which detail is actually wanted , it is quite common to use this as the key zone . In this example ( 3 ) , however , the immediate foreground is critical , for while it does not cover any significantly interesting detail to merit Zone III , it should have at least a hint of texture in the final print . So , as a first experiment , by placing the foreground in Zone II , everything else will fall in its own particular zone . This creates a problem with this scene , because the areas of the sandstone cliffs and rocks inevitably fall in Zone IX , which means that their texture will not register ( 4 ) . In other words , the contrast range in the subject is too great , a common problem .
Stage 3 : Unless something is done to alter the high contrast , either in the subject , the negative or the print , we will have to compromise by sacrificing detail at one end of the scale . In this example , it would certainly be better to sacrifice the foreground shadow detail ( 5 ) . By moving everything down one zone , the foreground becomes nearly black ( Zone I ) , but the cliff highlights become a satisfactory Zone VIII ( 6 ) .
This completes the visualization , and all that remains is to make the exposure . We have calculated how the final print will look before even taking the shot - the essence of the Zone System's use .
THE ZONE SYSTEM
For really fine control over exposure , entire systems have been invented at different times . The most famous of these is the Zone System , used by one of the greatest black - and - white photographers , Ansel Adams . This is certainly a more complicated approach to exposure than is usual , but it does make it possible for the photographer to be in complete control of the tonal values in the image . It takes time , and so is best suited to the photography of static scenes , such as landscapes and architectural subjects .
The Zone System assigns all the levels of brightness in a scene , and all tonal values , to a scale of ten steps . Each of these steps is exactly one stop different from the next , and the scale goes from pure black to pure white . As you can see from the strip ( left ) , Zone 0 is solid black , Zone V in the middle is an average mid - grey , and Zone IX is pure white . By assigning the important tones in the scene to the appropriate zones , it is relatively easy , once you are experi- enced , to see how the contrast range of the subject fits that of the negative and the print .
In many photographic situations , contrast is something of a problem , or at least demands careful attention . A typical scene has a contrast range of about seven stops , and so covers seven zones . A normal black - and - white negative , together with a typical Grade 2 printing paper ( this is the normal grade ) ; can handle this range , but it is important to place the zones correctly .
One of the most important zones is III - textured shadow . This is the value at which dark details can just be seen , and is generally thought of as being a tone that should be preserved in the print . This zone is 2 stops darker than average , and a typical procedure would be to measure it with an exposure meter and then adjust the settings on the camera to 2 stops less than the one indicated .
Comparing the brightness levels in the scene with the 10 - step scale shows which parts , if any , will fall outside the film's brightness range . Treat a medium- speed black - and - white negative film , developed and printed normally , as having a range of seven stops .
The Zones
0 Solid black ; the same as the film rebate ( edges )
I Nearly black ; just recognizably different from Zone 0 .
II The first hint of texture but nothing recognizable III Textured shadow ; the first zone to show recognizable shadow detail .
IV Average shadow value on Caucasian skin , landscape foliage and buildings .
V Middle grey ; 18 % grey test card ; the ' pivot ' value ; light foliage ; dark skin .
VI Caucasian skin ( 36 % reflectance ) ; textured light grey ; shadow on snow .
VII Light skin ; bright areas with texture , such as snow in low sunlight .
VIII Highest zone with any texture .
IX Pure untextured white ; little difference between this and unexposed paper .
ABOVE A typical scene with a contrast range of approximately seven stops . Fortunately , a typical black- and - white negative coupled with normal Grade 2 printing paper can handle this , although it is important to place the zones correctly .
RIGHT Zone III , textured shadow , is one of the most important , since it is the value at which dark details can just be seen . Its dominance in this portrait made it vital that it should be preserved in the finished print .
This sunlit scene covers many brightness values - in other words , it has a high contrast range .
Because we are discussing the tonal reproduction that a photograph offers , the original subject is represented here as an illustration ( 1 ) .
Stage 1 : Using the measuring methods described already , we can make a precise , objective record of the brightness levels in this original scene .
Different exposure meters record their information in different ways . The next picture ( 2 ) shows the scene measured in candles- per - square - foot ( c / ft ) ² , a universal measurement , but not one normally used by photographers , and also in f stops - by assuming a film speed of 100 ASA and a shutter speed of 1/125 sec .
Stage 2 : At this stage the photographer has to decide subjectively what are the important areas of the scene . Because Zone III ( " textured shadow " ) is defined as the darkest shadow area in which detail is actually wanted , it is quite common to use this as the key zone . In this example ( 3 ) , however , the immediate foreground is critical , for while it does not cover any significantly interesting detail to merit Zone III , it should have at least a hint of texture in the final print . So , as a first experiment , by placing the foreground in Zone II , everything else will fall in its own particular zone . This creates a problem with this scene , because the areas of the sandstone cliffs and rocks inevitably fall in Zone IX , which means that their texture will not register ( 4 ) . In other words , the contrast range in the subject is too great , a common problem .
Stage 3 : Unless something is done to alter the high contrast , either in the subject , the negative or the print , we will have to compromise by sacrificing detail at one end of the scale . In this example , it would certainly be better to sacrifice the foreground shadow detail ( 5 ) . By moving everything down one zone , the foreground becomes nearly black ( Zone I ) , but the cliff highlights become a satisfactory Zone VIII ( 6 ) .
This completes the visualization , and all that remains is to make the exposure . We have calculated how the final print will look before even taking the shot - the essence of the Zone System's use .
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