Don’t let its size fool you

The Pentax Optio S digital camera is so small that you can cover it completely with a credit card.

But this is no toy. The Optio S ($400, list price), which went on sale a few weeks ago, is a sophisticated camera. At its highest-quality setting, it takes 3-mega-pixel pictures, about 10 times the resolution of which the Palm or Nokia hidden cameras are capable.

The miniaturization -- it’s all of 2 by 3 1/4 inches -- comes at a cost. A regular-sized Nikon Coolpix 3100 digital camera that also takes 3-mega-pixel pictures can be had for $290.

But it’s hard to beat the Optio S for convenience. Touch the on switch, and the motorized zoom lens quickly moves into position. The screen lights up, and you’re ready to go. The shutter action is quick enough that the image you see on the screen is the one you capture.

Not incidentally, the Optio S is a beautiful-looking instrument, with a brushed-aluminum alloy exterior and intelligently laid-out buttons.

As a friend said, it looks more like a piece of jewelry than a gadget. If only more tech devices took that path.

-- David Colker