Exposing histograms

Histogram is the graphical representation of data showing the exposure (quantity of light reaching film) of a photo. Or simply said, it depicts the brightness level of a photograph.

A histogram is a simple representation of the tonal range of the picture. It provides us with the information about under or over exposure of a picture.

Where can I see it?

► It can be related only to digital photographs. And can be seen on the camera screen or can be seen using software like Photoshop.

What to look for?

► Always divide the histogram into three parts viz. Left, Center and Right.

•When reading histogram one should look out for spikes (peaks) and their tendency.

 •If you see more spikes to the left of histogram it would imply low key photographs meaning the photo is underexposed. Other way to look at it is contrast is dominant than brightness.

•Spike at middle would indicate mid tones dominance.

• If you see more spikes to the right of histogram it would imply high key photographs meaning the photo is underexposed. Other way to look at it is brightness is dominant than darkness.

•Well-exposed images have smooth peaks and troughs all the way across the histogram. (Remember the general rule to get a hump at the middle denoting uniform distribution).

•However, smooth peaks do not guarantee perfect exposure. For example, if you want to shoot bright object (say snow) but have histogram with uniform brightness distribution, it is time to know your exposure is no good.

Snow is never dark and night is never bright.

Should I care? 

► Don't get all Mathy !!