The Naughty Lens causes the difference you can see in the picture. On the left a picture taken without the lens where you can only see the clothes, on the right a picture with the lens where you can see behind the clothes, good or bad? That's your call...

Kaya are the producers of this wonderful lens, and I wonder if they will be in trouble soon. They called it Infrared See-Through filter PF and there's an overview of the product telling what's the function/how it works.

But to simplify it:

What's the function: The PF is a special optical device that helps to visually penetrate an object's surface in order to view whatever lies below. The PF makes it possible for you to see images that are normally invisible to the human eye.

How it works: Perhaps you are wondering what makes this ability possible. The answer lies in infrared rays. - Not so easy, there's more detailed information on their site.

A list is available to check if the camera will work with the lense, and the prices vary from $139 to $153. Order here

Take a very good look at the lens in the image below, and if you see anyone staring at you with a camera and the lense inserted, you know what to do.

Via GeekBlue

PS - I know this is old news, because there were other lenses and cameras in the past that made this available, but still it's always good to talk about it. And I thought it would be a good post for a sunday.