A cheap camera – this is one of the best presents Eames Demetrios remembers receiving from his grandparents, American mid-century modernists Charles and Bernice Alexandra “Ray” Eames. It’s not exactly what one would expect to hear of a duo who created an impressively varied creative portfolio, which includes some of the most iconic furniture designs of the 20th century, as well as works spanning architecture, film, exhibition design and toys.

With a laugh, Demetrios – who was recently in town for the launch of the ongoing Essential Eames exhibition – explains why “one of those very basic 35mm (camera) models that entered the market in the mid-1970s” was exactly what he needed as a 14-year-old preparing for a trip to the South Pacific to swim with a 9m-long whale shark.

He recalls: “Charles told me, ‘I’m worried that if you borrow your parents’ Nikon, you’ll be so afraid of dropping it in the water that you’ll never take it out of your room. I’m going to give you this camera, so don’t worry if you drop it in the water because it’s not worth very much.’

“Many grandparents might have thought, ‘What’s the most expensive camera we can get for our grandson?’ But (Charles) and Ray thought more clearly: ‘What does Eames really need for this trip?’”

The anecdote is reflective of the design philosophy of Charles and Ray Eames, for whom function invariably took precedence over form. As the director of Eames Office, Demetrios – who is also an artist and filmmaker – travels the world sharing and developing his grandparents’ considerable legacy.

Consider, for instance, one of their most well-known designs, LCW, which stands for Lounge Chair Wood (clearly, their practical attitude to design extended to the naming of their products). Developed as an affordable, high-quality chair that could be mass-produced, the plywood design – which comprises a seat and back joined by a spine – was the result of five years of pioneering experiments with wood-moulding techniques.

In 1999, Time magazine hailed the LCW as the best design of the 20th century – marking the enduring relevance of a chair created in 1945 and reaffirming Ray’s declaration: “What works good is better than what looks good, because what looks good can change, but works good will still work.” Today, the chair – along with many other classic Eames designs – is manufactured in collaboration with Herman Miller and Vitra.

To shed light on his grandparents’ profound knowledge of what “works good”, Demetrios refers to Mathematica, an interactive exhibition that the Eameses designed for IBM in 1961. He says: “They never delegated understanding.

“They didn’t say to the mathematicians, ‘Tell us what to say and we’ll make it look pretty,’ which is often what designers do. Instead, they wanted to deeply understand for themselves so that the design of the exhibition could come directly from their own learning and understanding.”

Arguably, it was this insatiable curiosity that led the couple to make their creative mark in a whole range of other fields: Working with moulded plywood lead to breakthroughs in moulded plastic and fibreglass; a passion for photography paved the way for filmmaking; and a penchant for toy-collecting led to toy designs. For the designers, function was paramount in the design process – but fun was never far behind.

Sharing another camera-related anecdote, Demetrios recalls how “cool” it was when Charles showed his grandkids a Polaroid SX-70 camera, a year before it was launched publicly. The proud grandson explains: “(Charles and Ray) had been asked to make a film for Polaroid. “(Charles) had such a great smile on his face because he had something fun he wanted to share with us.”