ISO

ISO is often described as the sensitivity of the camera's sensor to light. Usually in the write in the numbers 100, 200, 400, and so on

Number 100 (there are some cameras that have a smaller ISO number), require more light intensintas with a low level of sensitivity of the sensor to produce a photo / image the right light (proper exposure). And vice versa of the ISO number (eg 3200) has a high level of sensitivity and a light sensor that reatif bit to get the right picture of light. This effect on the resulting image.

As such a low ISO requires more light with a high level of sensitivity of the sensor. The resulting photo will be relatively clean (relatively free of noise), with richer colors (a lot) and bright. Not the case with when we use a higher ISO number. With this level of sensitivity to higher light, but require low light intensity, photo generated relatively less clean (relatively more noise it).

Night Photo ISO 3200/f2,2

Keep us always in a low ISO number. Between 100-200 for normal limits or to limit the number 400. But one day we are required to use the ISO greater numbers, especially to reduce camera shake because the shutter speed is very slow and at times shooting in low light.

Do not forget to incorporate a combination of numbers shutter speed, aperture and ISO to get a better photo.