Adam Schofield, 42, is colour blind and finds it difficult to mix paints so uses software on his iPad to create the life-like portraits.
After news broke of the 58-year-old TV star’s death from cancer last month, the Ossett postie decided to complete the painting which he had already started some time ago.
It has now got more than 3,000 likes on his Instagram page - more than any of his previous pieces.
He said: “I’ve always got something on in the background when I’m working, and nine times out of 10 it’s either Sean Lock, Bob Mortimer or music. I’d already started it and it was three-quarters finished so when he died I thought it would be a nice tribute.”
With a degree in fine art, Mr Schofield fell into the postal service because his dad worked there, but his passion remains painting.
He discovered digital painting about eight years ago, which he says was ideal because of his struggles with recognising colours.
He said: “I thought digital painting could be it, because you don’t have to mix colours.
“It’s just like painting once you know what you are doing with it.
“I have been doing them on and off for a while when during lockdown I was off so I said I was going to do one every day for two weeks to see if got things going.
“I was going to give it up, and the very last one of Fearne Cotton, (radio DJ) but she shared it on Instagram and it went mad.”
He has also been commissioned to paint portraits of TV star Davina McCall, but his latest work has attracted the most attention.
His Sean Lock portrait is to now be raffled off with the proceeds going towards Macmillan Cancer Support.
Tickets can be bought through Raffall.com by clicking here and cost £1.50 each.