What exactly is the ISO in a digital camera? What does it do?

Answer 1

http://www.photoxels.com/tutorial_iso.html

Answer 2

It's supposed to be the same as the ISO for camera film. It allows the photographer to decide on a tradeoff between the amount of light and picture quality. To make a good picture, a camera needs a lot of light. If you have plenty of light, you get a good picture with good quality (meaning low noise). This would be a low ISO number like 100. Let's say you don't have so much light. If you take the picture at ISO 100 still, what will happen is the camera will take the picture over more time and anything moving will appear blurry. Instead, you can use a high ISO number, like 400. This picture will not be as blurry because the picture was taken faster, but it won't look as good because there's more noise. I have a digital camera that goes from 80 ISO to 1600 ISO. That means when there's lots of light, or I'm using a tripod and photographing a stationary object I can use the 80 ISO and get a picture with very low noise. It also means if I want to take a picture in low light where I'm not allowed to use a flash (like a live show or a museum) I can turn it up to 1600 ISO and get an image that is not blurry but kind of fuzzy. By the way, I have the Fujifilm Finepix F10 and this is exactly why I bought it. Lower end digital cameras just go from 100 to 400 ISO. The newer Fujifilm Finepix F30 goes up to 3200 ISO. I'm sure it would make ugly pictures, but we're talking about getting pictures where other cameras can't.

Answer 3

Are you familiar with film photography? ISO is the number used to denote a film's sensitivity to light. 100 is not very sensitive, 1600 is very sensitive. For example: say you take two exposures, both with a shutter speed of 1/15 second. If one is at f2.6 and with ISO 100 film, and the other is at f11.0 and with ISO 800 film, they will be about the same exposure.

In a digital camera, you can't switch film, you have to use the same photo cell. So, a higher ISO simply amplifies the signal from the chip, much like when you turn up the volume on your stereo. However, when you amplify the signal, you also amplify the "noise." So unless you're shooting with a good SLR with a CMOS chip, higher ISO pictures will not look as clean or as crisp as ones at a lower ISO. Nonetheless, the advantages to shooting with a higher ISO are you can speed up your shutter speed and avoid motion blur, and if combined with a flash, you can do things like pick up the color of the sunset in the background as well as getting your friend in the foreground.

Hope this helps!

Answer 4

ISO (Sensitivity)
ISO is the number indicating a digital camera sensors sensitivity to light. The higher the sensitivity, the less light is needed to make an exposure.

Digital cameras automatically select the ISO but most have a setting to change it manually. Auto ISO generally works best for bright scenes.

Shooting at a lower ISO number requires more light than shooting at a higher number. Lower numbers result in images with the least visible noise, which is desirable.

The higher the number, the more noise. The amount and degree of noise varies from camera to camera.

Digital single reflex cameras (dSLR), because they have larger sensors, are best for producing noise-free images. However, some consumer digital cameras now have improved sensors that produce acceptable images at higher ISO.

Answer 5

ISO is strictly that: the commonplace of the captured image on digital "action picture"; no diverse from digicam roll action picture. ISO of 4 hundred, frequently, is the "all-purpose" exposure putting--purportedly suitable in the two organic and synthetic (flash) lights. ISO 800 is on your photos in darker settings, suitable used with a tripod and distant shutter launch. ISO one hundred, for my area, is the suitable putting: it quite is for use with flash lights. With a tripod, you may take a image with no flash, and get a tremendously respectable/consistent with possibility dark--yet clean non-grainy image.

Answer 6

ISO means sensibility, it calculates how much light the camera will receive and it has nothing to do with the time of exposure.

I can explain it better in portuguese.

:-)