Casio EX-S500 AutoFocus Noise

This is a fairly new camera and there is not much owner information available. I did not find any reports of what you described.

You could go to a camera store and try out one of their S500 cameras and see if it makes such a noise.

You could contact Casio and ask them:
http://www.casio.com/index.cfm?fuseaction=support.home

Click on the "Contact Us" link.

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I feel exactly the same thing about the autofocus noise.. it's kinda loud comparing to others. I wonder if there is any firmware upgrade that can fix it. I am already on the latest firmware 1.02.

=(

While the noise can be annoying, it is normal in the AF focus setting. In the manual, it mentions the PF Focus mode, Page 76. It is slower than AF, but the noise is gone. I have not noticed a huge difference in the focus quality between AF and PF, but PF is slower. Everything is working as intended.

There is nothing wrong with the camera. Personally, I want the AF to be fast, and I have a HD Camcorder, so this S500 is not my video camera. I use it because it fits in my pocket where my main camera (Canon EOS 1D Mark II) is not something I can take to work on a regular basis.