The ISO setting can be compared to film speed on a 35mm film camera.
If you are shooting a 35mm film camera in low light, you would use a faster film. With a digital camera you can just raise the ISO setting.
With the digital camera, you should leave the ISO setting at it lowest setting (usually 50). When you get into a situation that requires more light, raising the ISO setting provides more light (in a sense).
The higher you set the ISO setting the more likley that you will get "noise" in the darker areas of the photo. With 35mm film, high speed film you would call it "grain".
Some noise is better than no picture. There is software available to remove noise from a photo.
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Understanding shutter/aperture settings:
Here is a link to a site that covers this subject:
http://www.pbase.com/otfchallenge/the_basics
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Hi friends:
I bought a Panasonic Z 5 recently. Though there is a auto mode, I want to learn to start using manual settings like using different ISO settings for different speeds, shutter speeds etc.
Could you please provide me a link which describes these? Atleast what ISO to use for different scenes?

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