Appearances can be deceiving

Kim Kardashian has practically made a living from her curvaceous figure.

But the E! network celeb was looking a little less shapely in Complex magazine in April.

Her body was reduced about a dress size, and her legs were smoothed to near-perfection.

How did readers know? Complex accidentally posted a pre-Photoshopped image of Kardashian on its website - before her thighs, arms and waist had been digitally sculpted.

In a matter of hours the photo was gone.

But in that brief time span, those who spotted it got a little reminder that we should think twice about taking photographs at face value.

"My belief," says Scott Kelby, president of the United States Association of Photoshop Professionals, "is that every single major magazine cover is retouched.

"I don't know how they couldn't be."

But don't stop there.

Aside from newspapers, most of which do not permit photos to be manipulated, is quite possible that the vast majority of images seen in the public arena have been altered.

Photoshop, the go-to graphics editing program that got a foothold in the 1990s, has become so ubiquitous that most of us gaze at faces, bodies and landscapes without registering that wrinkles have been diminished, legs lengthened and the sky honed to a dream-like shade of blue.

While some laud Photoshop for its ability to allow people - and things - to look their best in a photograph, others see it as a vehicle for feeding society's desire for uber-perfection.

"I think the perfect bodies we're seeing in magazines that are Photoshopped have a terrible effect on how women feel about their own bodies," says Prof Montana Miller, assistant professor in the department of popular culture at Bowling Green State University in Ohio.

One theory about retouching in advertisements is that it's done to create an aspirational concept of beauty that inspires women to buy more products.

Prof Miller has heard another: that the goal of showing perfect images is to make women feel bad about themselves - also making them buy more beauty products.

Mr Kelby, who writes a blog about Photoshop, doesn't believe it's a malevolent force.

He sees it as practical, and cites the example of singer Faith Hill.

In 2007, the fashion website Jezebel posted unaltered images of Hill that were shot for a Redbook magazine cover.