Photographers and editors have declared themselves impressed with the "point and shoot".
Elliot Wagland, The Huffington Post UK's picture editor, said: "The pictures are spot on, the images are perfectly backlit and capture the love of newborn parents posing proudly with their newborn son."
The more formal arrangement
"These images capture the young family looking happy, relaxed and enjoying time with their son," he continued.
"Maybe Mr Middleton should take the age old showbiz advice of never working with children and animals, as their dog Tilly appears to be fast asleep compared to the media savvy Lupo. Keep up the good work Michael."
Martin Keene, head of pictures at the Press Association, said the photographs were impressive. "Any photographer would have been pleased to have taken them," he said.
Celebrity photographer Brian Aris told the Daily Mail: ‘It’s an unusual decision but perhaps reflects the young approach that Prince William wants to bring to bear.
"The decision to take them in such an informal manner means they, perhaps, lack the level of gravitas that would normally be expected.
"But on the whole I would say this is quite refreshing."
He added: "Taking a professional portrait of a young baby is quite an intrusive procedure, given the lighting and strobes you would need.
"So perhaps they have had the right idea after all. It’s just a different approach and the images are rather charming."
Lupo and Tilly appeared less interested in the photo than the rest of the family
"These photographs are typical of what family members take," said the Mirror's royal photographer Kent Gavin.
"The first is a little soft in focus on William and Kate, and I am not sure why the dog is in the photograph. I guess the reason Kate's father chose backlight was to avoid bright sun on little George.
"Back-lighting is always a little tricky for the non-professionals but it does give a nice result. Photographing against the sun needs a fill-in flash.
"Another option would be to use an area in shade away from harsh light. My professional view would be to see more of baby George - perhaps between William and Kate higher up."
Middleton follows a long line of photographers to have captured important images of members of the royal family.
Little is known about how much experience the British Airways flight dispatcher-turned-businessman has behind the lens, but as the first official photographs to be taken of the future king, the pictures are sure to have their place in history.
The intimate family portraits were taken in the garden of the Middleton family home in Bucklebury, Berkshire, earlier this month and for Middleton, they are not only of a future monarch but of his first grandchild.
The relaxed images of the smiling couple evoke memories of the Duke and Duchess of Cambridge's official engagement photos, shot by celebrated fashion photographer Mario Testino.
Other notable photographers of the most famous family in the world include Lord Snowdon, who was a member of the royal family by marriage.