exposure

[paulmitchell1984]

i m ay have missed a thread, if so im sorry

when monitoring for exposure, ive read in another thread that some poeple concentrate the the right of the meter and some to the left.

Now on my d90 im assuming this is the graph type thing.

But how do you concentrate the exposure to each side or is it a case of movng the camera around.

this is probably a simple question, and i apologies again if this has ben stated.

Paul

 

[Tom Harper]

I think what your talking about is exposing to the left or the right which refers to the histogram. Some people will slightly overexpose a shot so the histogram is more to the right on thier screen. This is done to help bring out the details in the shadows that might otherwise have been lost and was popular with film users as the chances of overexposing brighter areas like sky was less likely than it is with digital.

Exposing to the left is done to stop blowing out highlitghts by slightly underexposing the shot.

 

[Bristolian]

i m ay have missed a thread, if so im sorry

when monitoring for exposure, ive read in another thread that some poeple concentrate the the right of the meter and some to the left.

Now on my d90 im assuming this is the graph type thing.

But how do you concentrate the exposure to each side or is it a case of movng the camera around.

this is probably a simple question, and i apologies again if this has ben stated.

Paul

Hi Paul,

I think you are talking about the histogram. The base line of the histogram is the dynamicrange of the sensor with dark on the left and light on the right. The vertical axis shows the number of pixels in each part of the dynamic range. Peaks in the graph simply show where there are large numbers of pixels receiving light in that particular range.

For correct exposure (EV0) the graph should extend from the left side to the right side of the base line without any peaks/spikes at the extreme ends. Spikes or peaks at the extreme left would indicate that there are shadowed areas without sufficient detail in them to differentiate between pixels. Conversely, spikes/peaks at the extreme right shows there are bright areas of the picture where there is no detail - what is commonly referred to as blown-out.

When people speak of exposing to the right they generally mean making sure that the graph goes all the way to the right (without any spike at the extreme) which ensures you have the widest range of detail in the picture. When the graph stops short of the right hand side then the picture is underexposed and will appear darker and contain more noise. A gap at the left edge is overexposed and will be blow-out.

To move the graph more to the right you have to adjust the exposure to let in more light (slower shutter speed, wider exposure, higher iso); the opposite is true if you want to expose to the left.

Hope that helps

 

[paulmitchell1984]

It is the histogram that im thinking of, Thanks guys,

Bristolian that explination is great thanks, makes perfect sense

 

[EdBray]

It's still better to expose correctly though!

Might be worth a read!