This sounds like it might be a defective CCD imager. If so, Canon should fix this for you for free, including free shipping both ways. This is regardless of your camera's warranty status. Please check the following two links for more info:
HI I have a problem with my camera powershot A 70, in the case of image capture are not showing in...
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HI I have a problem with my camera powershot A 70, in the case of image capture are not showing in the the screen, I want to know the causes of this problem. Why cameranoperate without the pictures on the screen outside
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