You never can tell: George Bernard Shaw, the secret snapper

George Bernard Shaw once wrote: "If Velasquez was born today, he would be a photographer and not a painter." But the Irish playwright may also have thought his true calling lay behind the camera, according to researchers who have rediscovered more than 20,000 of his photographs.

The remarkable archive casts new light on the life of the writer by revealing his propensity for surfing, experimenting with photographic techniques and chronicling his existence at the heart of British intellectual and cultural life in the early 20th-century as much through the lens of his Box Brownie camera as his writing.

Previously unseen images of Shaw relaxing with the composer Edward Elgar and leading socialist thinkers Sidney and Beatrice Webb, as well his haunting pictures of a mist-shrouded Thames and ghostly self-portraits, show how the playwright became fascinated with all aspects of photography and subsumed it into his daily life.

The first 1,000 prints from the collection have been placed online in a joint project by the National Trust and the London School of Economics, which was co-founded by Shaw, after the pictures which had lain untouched and uncatalogued following his death in 1950 were pored over by researchers.

Fiona Hall, curator for the Trust, which was bequested the playwright's home, Shaw's Corner, in Hertfordshire, said: "Shaw was incredibly curious about many, many things but one of the things he really latched on to was photography. The pictures show a real contrast between the private man and his public persona.

"The shots of Shaw the celebrity show an unsmiling and smartly-dressed figure propped on a cane. But these photographs reveal a very different person, who went surfing, picnicking and imitated the poses from famous sculptures. The collection has the potential to revise our understanding of Shaw and those who knew him."

Armed with his cameras, Shaw seems to have been enthusiastic in taking snapshots of the heroes of his age, including the film star Vivien Leigh and authors HG Wells and JM Barrie.

The playwright also took multiple photographs while on his travels abroad to New Zealand, South Africa and across Europe with his wife Charlotte.

When asked why he had taken up photography, Shaw once said: "I always wanted to draw and paint. I aspired to be a Michael Angelo, not a Shakespear [sic]. But I could not draw well enough to satisfy myself... So when dry plates and push buttons came into the market I bought a box camera and began pushing the button."