What are ISO's on a digital camera? I need a simple, straight to the point explanation.?

Question

What are ISO's on a digital camera? I need a simple, straight to the point explanation.?

Answer 1

ISO is a setting of how sensitive the camera's digital sensor is to light.  Think of it like the speed of the film.

That's about as simple as I can get it without providing the explanation below.

The lower the ISO, the less sensitive... which means the less likely the sensor has of reading an incorrect value... i.e. less noise.

The higher the ISO, the more sensitive... which means the more likely the sensor has of reading an incorrect value... i.e. more noise.

Answer 2

In digital they call it ISO and in film they call it ASA.

Answer 3

The ISO is the light sensitivity (film speed). The lower the number, the more light that is needed to get a good exposure. For example, on a bright sunny day outdoors you would want to use an ISO of 100 or 200, in a dimly lit room indoors your would want to use an ISO or 400 or 800.

If you ever bought a disposable camera or film for a 35mm camera, you may remember the large numbers on the box... 100, 200, 400, 800, etc.

Answer 4

ISO is analogous to ASA (film speed). Historically film speeds were in the 60 to 100 range with fast films up to 400ASA. The light sensors in today's digital cameras run generally from ISO 200 to 1600 which relaxes the need for faster lens (ones with lower f-numbers like 1.2, 1.4, 2.0).

Answer 5

Lower ISO means you need more light to get a reasonable image.

High ISO means that you can take pictures in lower light conditions but a side effect is that too high an ISO will give you noise or grain on your pictures.

Have Fun

i.o.l