Not likely. Here's why. To keep the size and wieght of the camera down, most are designed to be used for a few minutes and not to be left on for hours. The heat buildup in these cameras is why they can't be used as a webcam.
Since I would not want to have a double the wieght camera, that relegates such a model to very low production quantities and will knock it off the market very quickly.
Hope this helps you understand why digital cameras and camcorders are often poor canidates for webcams.
Bob
Is it possible for me to use my newly purchased A75 as a webcam? I love this camera and I love this site... I've been using this site for the last 6 months to research the perfect camera for me as I saved up the dollars...

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