can anyone explain ISO?

[reefermike1]

curious what iso settings are, what they do, and how to use it. i have a cannon a630. thanks.

[Doug1]

ISO on a camera refers to "Film Speed Settings" or sensitivity to light, the higher the ISP the more sensitive, like on film cameras where 400 or 800 speed film alows you to shoot indoors with little additional light

[reefermike1]

so then a lower iso would be better for pics of the tank with the main lights on?

[tabblet15]

Yea... the more light you have the lower ISO you should shoot in. Always shoot the lowest ISO that the lighting will allow because the higher the ISO the "grainer" (fuzzier, etc) you photo will look. I would not go over 800, even then your pushing it. Just play around with it and you'll see what I'm talkin about.