Filter Use with Lens Adapters

I recently stopped at the local camera shop in search of a polarized filter. We put the Canon lens adapter on my camera and proceeded to screw a UV filter onto that. These people didn't really seem too bright (considering they were running a camera shop). It appeared that when we zoomed the camera that the internal lens housings came very near the filter. It was hard to be sure that they weren't hitting the filter. Am I doing something wrong? It's hard to believe it should be this close. I assumed you could just screw a filter onto the lens adapter directly (58 mm by the way)? My additional concern is that it seem some circular polarizers are thicker than UV filters, so they may be even closer to contacting.

Please help!

Sorry , no advice - but you've scared me now!

If the lens housing hits the filter, it should retrack back.
Correct me if I am wrong.

This is correct.

Put a small drop of water on the Canon len in the middle, and let it extend normally.If the drop is still there, then the len is not hitting the uv or polariser.

Rodenstock.

if the lens touches the filter on the adapter even slightly, it will retract the lens and shut the G3 down. This is a safety built into the G3 to protect the lens. If your camera is not shutting down, the lens is not touching.

Thanks to all. I didn't know about the safety mechanism.

Much appreciated.

Kip