ISO

Your ISO will shows if your photo is grainy or not. Your ISO also depends on what you are taking a picture, how far your subject is, and if the amount of light. Low ISO is less grainier than high ISO.

Low

This photo has a Low ISO because I had the perfect Aperture which impacted the ISO and the ISO was dead in the middle which shows in the picture that the phot is not grainy.











High

The photo has a High ISO because I took this picture as a close up with a Low ISO and with a High Aperture which impacted the sensitivity.












Under

Here is a reference sheet for your ISO levels.