What is "ISO speed" and how does it affect my digital camera's photos?
It's just like the ISO speed was on your film. ISO tells us what sensitivity or how much light is required to make the picture. Now on film, ISO, higher ISO, gave us a grainier less clear picture; a lower ISO gave us better color and better clarity. The same happens in digital. As you turn down the ISO you're going to get clearer, crisper, better colored pictures. As you turn up the ISO, it needs less light to take the picture, but we get digital noise, looks like kinda snow on the TV set, you get these kinda colored artifacts, kinda freaky-deaky in the picture, thats what grain or noise is on your digital picture. My recommendation to you is: always set the digital camera to the lowest or next to the lowest for general purpose photography. If you shoot inside without a flash, indoors, you know, like a basketball game, hockey game, you know, indoor play or something like that, then you need to boost the ISO. But one thing I need to tell you is before you do that is you have to take a test on your camera because some cameras have a very low threshold for noise or the picture quality gets pretty bad, pretty quickly. So, you have to test with your individual cameras. You need to also note that the smaller cameras, the compacts, give more noise then the SLRs do, and that goes back again to the size of the imaging chip with a small imaging chip we get more noise or more grain, With the SLRs and the bigger imaging chip we get less noise and therefore we're able to boost the ISO higher and give you more low-light capability.
