Lesson Three: ISO, Grain and Noise

For lesser noise keep ISO levels as less as possible

ISO level 100 is considered normal and it goes like 200, 400 etc. Higher ISO level means faster films. Faste films mean that amount of light to be collected is not high because you have sacrificed lesser noise for speed. That is you can have faster shutter speeds, lower apertures in dark light, ofcourse you will have higher noise in the picture.

In circumstances like a sports photo in a dark lighting would you want to get higher shutter speeds to freeze shots of a moving object. And you would achieve this by bumping up the ISO.

Grain is the word from film days and finer grain is associated with lower ISO or less sensitive films. By less sensitive means lesser sensitivity to external light.

So, now, we have another parameter added to exposure equation.

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