That camera should produce excellent photos.
Since you bought the camera last night, I assume you are writing about photos you took last night.
If you took photos using the flash, they should turn out fine.
If you took photos with the flash turned off, you will likely get noise in the photo and some blurring due to camera movement and slow shutter speeds.
Take more photos today, outside.
Your old camera was a bit larger and easier to hold steady.
These small cameras take more effort to hold them properly and steadily.
Make sure that when you press the shutter button down you don't also push the camera down. Hold the camera so that your right thumb is on the bottom of the camera and then you will be pinching the shutter button, between your forefinger and thumb, therefore not moving the camera.
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I got the SD800IS last night to replace my favorite camera (Kodak Z730) which was ruined in a downpour. I am very unhappy with the photos I took. Nothing is crisp and everything has noise and color distortion. Any suggestions? I have tried auto, scene select, and manual. I read the guides cover to cover too.

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