It’s Important to understand that there are two different ways to calculate the light in order to achieve a properly exposed pictures in photography.
we can calculate the light reflected by the subject,which is how the light meter in our camera works, or we can calculate the light falling on the subject using a handled light meter at the subject position.
The major element to understand is that meters are calibrated to measure a neutral gray tone.
A reflected light meter "assumes" that the subject is reflecting the same amount of light reflected a gray card.
With the photometer reflex camera,if the subject is bright white photographer must select an aperture of about 2 stops larger than the meter indicates.This is because the camera "thinks" that is looking neutral gray is not bright, so will indicate an opening to expose the scene as gray, not white.
If you are shooting a darker than neutral gray subject - for example,a black bear in the dark forest, deeply shaded - camera meter can give a reading that the subject is exposed.This black bears should reflect less light than a gray card, but the camera still "thinks" the scene is of a neutral gray tone.
The same theory apply with portraiture.The photographer must understand this and increase or decrease exposure accordingly if they are relying on the camera meter,or use an incident light meter hand for more accurate results.In the measuring chamber may be further complicated depending on the measurement mode the photographer chooses.
The meter normally reads only the "constant" ambient light. we need a meter with measurement capability to measure flash instant burst of light from a flash or strobe light.
we can calculate the light reflected by the subject,which is how the light meter in our camera works, or we can calculate the light falling on the subject using a handled light meter at the subject position.
The major element to understand is that meters are calibrated to measure a neutral gray tone.
A reflected light meter "assumes" that the subject is reflecting the same amount of light reflected a gray card.
With the photometer reflex camera,if the subject is bright white photographer must select an aperture of about 2 stops larger than the meter indicates.This is because the camera "thinks" that is looking neutral gray is not bright, so will indicate an opening to expose the scene as gray, not white.
If you are shooting a darker than neutral gray subject - for example,a black bear in the dark forest, deeply shaded - camera meter can give a reading that the subject is exposed.This black bears should reflect less light than a gray card, but the camera still "thinks" the scene is of a neutral gray tone.
The same theory apply with portraiture.The photographer must understand this and increase or decrease exposure accordingly if they are relying on the camera meter,or use an incident light meter hand for more accurate results.In the measuring chamber may be further complicated depending on the measurement mode the photographer chooses.
The meter normally reads only the "constant" ambient light. we need a meter with measurement capability to measure flash instant burst of light from a flash or strobe light.
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