Voxpop – What is your favourite example of optical illusion in design?

‘Most designers can’t help wanting to surprise and entertain, from clever car park signage by Emery Studios to Massive Attack’s beautiful Collected cover that hid skulls inside flowers – the joy is in the moment of discovering the “illusion”. I often find myself analysing design pieces, particularly logos, trying to discover the idea (usually not worth the effort). Because, like spotting the bear in the Toblerone mountain (what do you mean “what bear?”), it’s the buzz of finding those hidden gems that makes me want to create a smile for others in my own work.’

Jack Renwick, independent designer

‘If you’d asked me this ten years ago I would have said anything by Japanese master of negative space and wit Shigeo Fukuda, whose work I pored over at art college having discovered him in a battered copy of “Smile in the Mind”. Three years ago I would have said the Milton Agency logo designed by one of our designers Tim – still my favourite logo to leave our studio. But today it has to be Noma Barr – in particular the dog sniffer from his ‘Cut It Out’ exhibition. Craft, intelligence and wit combined, just how I like it.’

Jamie Ellul, creative director, Magpie Studio

‘Design? Possibly not, but visually arresting nonetheless, the remarkable painting The Ambassadors by Hans Holbein stopped me in my tracks on an inaugural visit to The National Gallery in 1977. It is still one of my favourite optical masterpieces. A fairly formal portrait is turned on its head, literally, by the inclusion of what appears to be a stain on the carpet. However, on viewing from the side the “stain” reveals itself as a skull rendered in an amorphic perspective. A symbol of mortality? Holbein showing off his painting prowess? No one quite knows, but it still has the power to shock and surprise today, as it must have done some five centuries ago.’

Phil Carter, creative director, Carter Wong Design

When I think of the question, I think of Rene Magritte,M.C Escher, Bridget Riley, pavement artists, Victor Vasarely, Hans Holbein’s painting The Ambassadors, truck art and the German company Urban Screen. Their projection onto the Galerie der Gegenwart building is a feast of music, animation, art and choreography. But, the stunning illusion I love is Richard Wilson’s 20:50 piece of installation art at the Saatchi Gallery. You can smell it before you see it. Using highly reflective sump oil, the illusion of a room turned upside down is achieved with dramatic effect. Go and see it and experience the art of illusion!

Glenn Tutssel, executive creative director, The Brand Union