This could be due to any of the following reasons. 1) A dirty lens can cause whitish blurring of an image. 2) Light from the flash reflected back from the subject can cause blurring and a feeling that the image is out of focus. 3) In total darkness when AF measurements are impossible, the camera focuses for about 2 meters. Subjects that are closer or further will be out of focus. The Auto Focus Frame is red when AF measurements are impossible. In this case, use manual focus (MF).
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