The problems you list are certainly not normal for that camera.
But the description fits the problem of a fingerprint on the lens.
Look carefully at the front of the lens and see if you find a fingerprint on the glass.
Use a soft cotton cloth and your breath to clean the lens.
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Hi, I have just bought Canon POwershot SD600 2 days back. I have a problem with the images I have clicked. They have been clicked in broad daylight, but they are not very sharp, some of them are grainy and some of them seem to be oversaturated with color making it look unreal. There seems to be some focussing problem too. I shot them with auto-mode. Are there some additional settings I need to do ?
Thanks
Siddharth

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