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CHOOSING THE EXPOSURE
How much you can rely on the TTL metering system in your camera depends on its sophistication . Currently , the most advanced technique is multi - pattern metering , in which the picture area measured by the camera's meter , is divided into segments . Each of these segments is metered individually , and the pattern is then compared with similar patterns already programmed into the electronic memory . Certain patterns usually indicate types of lighting condition ( a dark centre and bright surround is typical of backlighting ) , and the exposure circuits react accordingly . Nevertheless , the foolproof method of getting the exposure you want is to know yourself more or less what it should be . To do this , practice taking readings , either with the camera's meter set to manual , or with a hand- held meter as a back - up .
AVERAGE READINGS
This is the standard method - an overall reading that averages everything in the shot . It usually works . One precaution in a scene with a bright sky is to meter the view below the skyline . Most TTL meters are biased for this anyway , but with a handheld meter , shade the top with your hand .
KEY READINGS
With this technique , you choose in advance the most important tone in the scene , measure that , and set the exposure to suit . Several cameras with TTL metering have this option , using a small central area ( or spot ) of the viewfinder Otherwise , the classic method is with a spot meter , which measures over a one degree angle of view . Doing this , you can ignore a strongly contrasting back- ground .
BELOW LEFT The best approach to low - contrast scenes such as this is to take an average reading . Since the vast majority of TTL meters built to cameras do this anyway , the risk of the exposure going astray for this type of shot is minimized . If a hand - held meter is to be used , shade the top with your hand ( above ) so that the reading is not overly influenced by the sky .
ABOVE The safest technique in this instance would be to take range readings . Take readings using an incident meter from the darkest and brightest areas , excluding reflections and deep blacks . Then , if the range between the two is no higher than seven stops for negatives and five stops for slides , calculate an average of the two .
RANGE READINGS
These are a kind of ' thinking version ' of average readings . The technique is to measure the brightest and darkest parts of a scene , excluding reflections and deep black . With an incident meter , measure the brightest lighting and the darkest shadow . Provided that the range between the two is no higher than seven stops for negative and five stops for slide film , the average of the two readings should give a reasonable exposure .
BRACKETING
Most professionals bracket exposures around what they judge to be the right setting . This involves taking a rapid sequence , changing the exposure between each by half a stop .
BELOW Night shots are notorious for providing exposure difficulties Here , it is advisable to bracket exposures , starting with a reading from the most important subjects and then bracketing , for example , two stops in either direction .
CHOOSING THE EXPOSURE
How much you can rely on the TTL metering system in your camera depends on its sophistication . Currently , the most advanced technique is multi - pattern metering , in which the picture area measured by the camera's meter , is divided into segments . Each of these segments is metered individually , and the pattern is then compared with similar patterns already programmed into the electronic memory . Certain patterns usually indicate types of lighting condition ( a dark centre and bright surround is typical of backlighting ) , and the exposure circuits react accordingly . Nevertheless , the foolproof method of getting the exposure you want is to know yourself more or less what it should be . To do this , practice taking readings , either with the camera's meter set to manual , or with a hand- held meter as a back - up .
AVERAGE READINGS
This is the standard method - an overall reading that averages everything in the shot . It usually works . One precaution in a scene with a bright sky is to meter the view below the skyline . Most TTL meters are biased for this anyway , but with a handheld meter , shade the top with your hand .
KEY READINGS
With this technique , you choose in advance the most important tone in the scene , measure that , and set the exposure to suit . Several cameras with TTL metering have this option , using a small central area ( or spot ) of the viewfinder Otherwise , the classic method is with a spot meter , which measures over a one degree angle of view . Doing this , you can ignore a strongly contrasting back- ground .
BELOW LEFT The best approach to low - contrast scenes such as this is to take an average reading . Since the vast majority of TTL meters built to cameras do this anyway , the risk of the exposure going astray for this type of shot is minimized . If a hand - held meter is to be used , shade the top with your hand ( above ) so that the reading is not overly influenced by the sky .
ABOVE The safest technique in this instance would be to take range readings . Take readings using an incident meter from the darkest and brightest areas , excluding reflections and deep blacks . Then , if the range between the two is no higher than seven stops for negatives and five stops for slides , calculate an average of the two .
RANGE READINGS
These are a kind of ' thinking version ' of average readings . The technique is to measure the brightest and darkest parts of a scene , excluding reflections and deep black . With an incident meter , measure the brightest lighting and the darkest shadow . Provided that the range between the two is no higher than seven stops for negative and five stops for slide film , the average of the two readings should give a reasonable exposure .
BRACKETING
Most professionals bracket exposures around what they judge to be the right setting . This involves taking a rapid sequence , changing the exposure between each by half a stop .
BELOW Night shots are notorious for providing exposure difficulties Here , it is advisable to bracket exposures , starting with a reading from the most important subjects and then bracketing , for example , two stops in either direction .
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