Kate Middleton's First Official Portrait Unveiled

(Image Credit: Sang Tan/AP Photo)

Duchess of Cambridge Kate Middleton and Prince William visited the National Portrait Gallery in London today for the unveiling of her first official portrait.

Award-winning artist Paul Emsley painted Middleton against his trademark black background with a slight smile, framed by her long locks.

Emsley said he wanted to capture Middleton's natural beauty. Emsley said he was originally going to paint the mother-to-be without a smile, but changed his mind shortly after meeting her.

"I think it was the right choice in the end to have her smiling. That's really who she is, I think," said Emsley, who was born in Scotland and grew up in South Africa.

Click Here to See More Photos of Kate Middleton Through the Years

Emsley also took liberties with Middleton's eye color, changing it slightly to match the blouse she is wearing in the painting.

While the painting reveals a more mature Middleton, art critics are slamming Emsley's work, saying it looks nothing like her.

"Seriously, as a concept, what is it? It's like a giant Polaroid. Like she went into a photo booth and had that picture taken and blown up to a huge size it would look more or less the same, wouldn't it," Waldemar Januszczak, art critic for The Sunday Times, said.

Middleton, 31, sat twice for the portrait - once in May and again in June. She reportedly described the work as "amazing," adding, "I thought it was brilliant."

William said, "It's absolutely beautiful."

It was a rare appearance for the Duchess of Cambridge, who was released from the hospital in December, as she battles severe morning sickness known as hyperemesis gravidarum.