From its humble beginnings in 2009 as an event championing so-called “smart lights”, Vivid Sydney has grown into a 23-day, multi-headed behemoth that now includes music, ideas and food programs. The heart of the festival remains the famous light shows – over 30 this year – which have morphed from focusing entirely on work by individual artists to a range of shows on a grander scale, often in partnership with private sponsors. Lightscape at the Royal Botanic Garden Sydney.

Credit: James Brickwood Last year ticket booths went up at the entrance to the Royal Botanic Garden and visitors were charged visitors to see one of the event’s most expansive works, Lightscape . The decision was criticised by some politicians . A second paid light show, Dark Spectrum, a 900-metre walk starting below Wynyard was also introduced.

This year another paid light event (although organisers say it is technically part of the music program) has been added. The Tekno Train is a “pulsing techno thrill ride” around the city’s rail network, costing up to $26 per ticket. The regular, and highly popular, light walk between the Opera House and Ultimo remains - which raises the question: is it worth shelling out for the paid events, or are you better off sticking with free experience? Dark Spectrum tickets will set you back between $35 and $46 dollars depending on the time of day you go, but can cost up to $154 for a family of four.

The near kilometre long walk is billed as “a secret spectr.