"We've just had Christmas, we've just had London and Westminster full of Christmas lights and Christmas cheer and then all of the sudden it goes a bit dark," Nickie Aiken, leader of Westminster Council, told Fairfax Media.

"It's the beginning of the year, people are thinking about their new year resolutions, it's the middle of January, they're probably starting to break them, so let's cheer ourselves up."

Cue Lumiere, featuring 58 light installations across six areas of London: the West End, Fitzrovia, Mayfair, Kings Cross, Southbank and Westminster. Some of the stand-out exhibitions include illuminated toads, flowers, butterflies and hares in Leicester Square, a giant ball over Oxford Circus and a constantly changing projection in rainbow colours across Westminster Abbey.

The light festival is a relative newcomer to London's rich cultural calendar, having started in 2016. Snow and heavy rain are not expected to deter the 1.3 million visitors organisers expect.

"The weather is a contentious thing; we've had heavy winds, but we didn't lose anything, so we're really grateful for that," said Helen Marriage from Artichoke, the artistic company behind Lumiere.

She said the festival was transforming London, even for Londoners.

"If you look at something like Westminster Abbey, where we are basically painting in light on the west front and on the north door with an amazing artist Patrice Warrener from France, a parishioner said to me, 'I've been in that building every day, I've never looked at the carvings on the front before.' "

While impressive, Lumiere is pint-sized in comparison with Vivid Sydney, which markets itself as the Asia-Pacific's annual "festival of light, music and ideas".

It runs for just four nights compared with Sydney's 23 days. Last year, 2.33 million attended Vivid - a record number - NSW Premier Gladys Berejiklian said.

This year, Vivid Sydney's 10th outing will run from May 25 to June 16.

"Vivid's a really great festival; it's very different from Lumiere because it has that whole music and talks and other element to it. This is just a pure light festival," Marriage said.

But she said that organisers of light festivals talk, collaborate, share ideas and artists' inspiration.

"It's really nice to know there's a family of festivals across the world," she said.

The downside is that the festival brings with it road closures across the theatre district in London's West End, one of the city's busiest parts, especially on the weekend.

Marriage said this and the permissions required to install lights around some historic buildings such as the Abbey, make the task more complex for the city of London.

Aiken said she believed Lumiere was still being tested, but she said it was worth the disruption and called for it to run longer in future.

"We will continue to do this. I think we need to extend it; four days is hardly anything; let's make it a week, let's make it two," she said.

"I think they're testing it out. It's one of those things that until you do it you never know how it's going to work out.

"It's getting bigger. Hopefully it will be bigger next year and then we can look at making it longer."

Asked why London was playing catch-up, Aiken responded: "Well, better late than never."

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