The Canterbury photographer who snapped four generations of the royal family for a new set of stamps kept his work secret for more than a year – even from his family.

Ranald Mackechnie, 55, will go down in history as the man behind the first stamp to feature the future king, two-year-old Prince George.

The Royal Mail issued the set of four portrait stamps today ahead of Queen Elizabeth’s 90th birthday, tomorrow.

They show Her Majesty, Prince Charles, Prince William and Prince George in the White Drawing Room at Buckingham Palace.

Mr Mackechnie, who lives in The Crescent in St Stephen’s, says he first found out he would be commissioned to do the work 18 months ago and took the photographs last summer.

He told KentOnline: “I had to keep schtum about it. John le Carré always said that if you tell one person you tell everyone so I kept it to myself and managed to do that.

“The family found out when we watched the news the night before and they went through the next day’s paper.

“But it’s all been incredibly thrilling and was an ambition of mine. Working on a stamp is a real landmark for any photographer or artist.”

The day before the shoot was to take place, Mr Mackechnie visited the palace to set up his equipment.

He says that by the time the four generations of the royal family walked in, he was “98% ready”.

Prince George was particularly interested in his lights and photographic equipment.

“It was an amazingly relaxing and light-hearted sitting,” he said. “They were comfortable with one another and behaved like any family with their conversation and jokes.

“The joy and energy coming out of George was fantastic" - Ranald Mackechnie

“It was much more relaxed than when I’ve tried to take pictures with my family.

“The joy and energy coming out of George was fantastic. It lifted the whole shot and the afternoon.

“He was on top form. He was quite fascinated by the lights. He took it all in his stride.”

Mr Mackechnie’s other work has included portraits of England sportsmen, historian David Starkey and football manager Harry Redknapp.

The cost of the royal stamps is £2.56.