Nokia apologises for 'faked' ad

The Verge tech site revealed the issue after it noticed a window reflection revealed a cameraman holding what appeared to be an SLR camera.

In a blog post the handset maker said it should have "posted a disclaimer".

The news threatens to take the shine off the launch of the Lumia 920 phone.

Investors had already shown doubts about whether the Windows Phone 8 handset could revive the Finnish company's fortunes, sending its shares nearly 8% lower on Wednesday.

In Thursday's trade the stock fell a further 6%.

'Faked' footage
The advert showed a man filming his girlfriend using the new smartphone while both of them were riding bicycles.

The footage cut from professionally-filmed material, featuring both actors, to what looked like it was the video captured by the man's Nokia device.

A split-screen sequence then showed what the smartphone's footage would look like with Nokia's optical image stabilization (OIS) feature turned on and switched off.

The footage was intended to support the firm's claim that its technology helped reduce image blur. It was shown at a press conference on Wednesday to support Nokia's boast that the Lumia 920 featured the best smartphone image quality on the market.

The Verge's article said: "too bad it's faked".

Nokia's blog acknowledged the problem in a post titled "An apology is due".

"We produced a video that simulates what we will be able to deliver with OIS," wrote the site's editor Heidi Lemmetyinen.

"Of course, hindsight is 20/20, but we should have posted a disclaimer stating this was a representation of OIS only. This was not shot with a Lumia 920... we apologise for the confusion we created."

Nokia also released footage that had been shot with the model.

The director of the UK's Institute of Business Ethics (IBE) said the affair was surprising bearing in mind the Finnish company had previously addressed what kinds of marketing materials should be used.

"It is good that Nokia has recognised how misleading their advertisement was and has apologised for that," Philippa Foster Back told the BBC.

"That is an important element in trying to maintain trust. The company does have a code of conduct recognising that 'high ethics means success' and states that the company 'conducts its marketing in a responsible way'.

"Whether oversight or deliberate, and sceptics might think the latter, Nokia has let itself down. The product will need, more than ever, to speak for itself."

The IBE receives donations from some of the UK's mobile operators but not the handset makers themselves.