- More than 1,000 visitors toured Rock Posters' Thornbury factory during Open House Melbourne 2026, with the greatest interest centring on the company's screen printing operation, which has been running since 1986.
- The refurbished SIAS automatic clamshell press remains in active commercial use, handling stock from 100gsm street poster paper to 5mm corflute, and offering capabilities beyond standard digital printing, including fluoro colours outside the CMYK gamut and heavier ink coverage.
- The screen printing process is deliberately labour-intensive, requiring separate screen preparation and a distinct press pass for each colour, meaning a two-colour poster requires two full runs through the machine.
- Artwork & Production Manager Luke Stewart noted that the creative constraints of limited colour palettes push designers to produce stronger work, while General Manager Marcus Seal said visitor response confirmed public appetite for things that are made rather than generated.
- The open day took place against a backdrop of growth in out-of-home advertising, with the Outdoor Media Association reporting net media revenue of $385 million in Q2 2026, up 5.58 per cent.
More than 1,000 visitors toured the Rock Posters factory in Thornbury during Open House Melbourne 2026, and the biggest queue formed around a printing method the industry has largely abandoned.
Rock Posters has been screen printing street posters since 1986. The refurbished SIAS automatic clamshell press at its Thornbury workshop still runs commercial jobs today, alongside a darkroom that has outlived the technology it was built for.
Visitors during Open House Melbourne were repeatedly surprised by how far the process sits from standard printing in 2026, and how rare it has become.
The press handles work up to 1500mm x 1000mm, on stock ranging from 100gsm street poster paper through to 5mm corflute. It earns its place commercially in the areas digital cannot reach: fluoro colour outside the standard CMYK gamut, heavier ink coverage, and the physical character of a screen-printed finish. RMIT has its art show street posters screen printed most years.
The process is deliberately slow. Screens are coated with emulsion in the darkroom, colours are separated and printed onto film positives, each screen is exposed under UV and washed out, then every colour is printed in a separate pass. A two-colour poster means two full passes through the press.
"If you want to keep the print cost down, you've got to build the whole poster out of two colours, and that forces designers to work out how to get the most from the ones they choose. It's always interesting to see what people come up with," said Luke Stewart, Artwork & Production Manager at Rock Posters.
That constraint is part of the appeal for designers. Every additional colour adds a screen, preparation time and cost, which pushes creative teams to get more out of a limited palette.
"There's a saying among traditional tattooers, bold will hold," said Stewart. "I take the same principle to street posters. Bold imagery, great contrasting colours, and the thing works on the street."
The work sits inside a growing category. Out-of-home advertising net media revenue reached $385 million in Q2 2026, up 5.58 per cent, according to the Outdoor Media Association.
Rock Posters has published a full account of the press, the process and its history in the Street Blog at rockposters.com.au.
About us:
About Rock Posters
Rock Posters is an independent Australian out-of-home media network with printing facilities in Melbourne and Sydney. Operating since 1986, they have produced street poster and large-format campaigns for clients including the National Gallery of Victoria, the Sydney Film Festival and the Australian Museum. Rock Posters won the Premier's Sustainability Award in 2022 and was shortlisted for the Australian Financial Review Sustainability Leader's Award in the same year.
Contact details:
Marcus Seal
General Manager, Rock Posters
03 9416 9966
