Theatre audiences are used to that pre-performance announcement banning all recording and photography.
But more shows are now inviting audiences to snap to their hearts' content after a performance.
When Andrew Lloyd Webber's Starlight Express rolled into Marina Bay Sands earlier this month, organisers allowed the audience to take as many pictures as they liked during curtain call.
This is not the first time Marina Bay Sands has encouraged photo-taking during the curtain call.
A Marina Bay Sands spokesman says that while they do not allow photography during the show, they have been using the curtain call opportunity to increase branding for select shows.
"The photo-ops are decided in consultation with artists and productions. In the past, we have allowed this for shows such as The Bootleg Beatles and The Phantom Unmasked as well as children's shows presented by Disney and Hi-5," he said.
At Singapore's key performing arts centre, the Esplanade, guidelines on photography during shows are made in consultation with artists and hirers.
Says Mr Ravi Sivalingam, 45, director of operations at the Esplanade: "We realise that the proliferation of social media and the branding opportunities that come with it presents certain upsides to allowing photography in shows.
"However, our first priority is always to preserve the experience for artists and the audience. We have found that most of our patrons agree with and are understanding towards our position on photography during performances."
Theatre groups, it seems, are cottoning on to the social media possibilities of Instagram and mobile phone photography.
While concerts have given up banning photography during gigs, near impossible to enforce in this age of camera-equipped mobile phones, photography during curtain calls is a relatively new practice for theatre.
Pangdemonium Productions, for instance, recently allowed photo-taking during the curtain call of Gruesome Playground Injuries at the Esplanade Theatre Studio earlier this month.
The post-show announcement said it was so that audiences could share the photos on social media platforms such as Facebook.
Actor and co-founder Adrian Pang of Pangdemonium Productions told Life! it has allowed photos only during the curtain call.
"During the show, it is an absolute no-no. We severely frown upon people who post on Facebook, text or tweet during shows. It is very anti-social and distracting for the actors and fellow audience members," said Pang, 47.
"While we have allowed pictures during the curtain call, we have to be mindful of context and whether it is appropriate or not."
The company is very active on social media and the recent policy of photo- taking during curtain calls was encouraged from April this year when it presented the play Rabbit Hole at the DBS Arts Centre. It has had positive responses to the practice from audiences.
TheatreWorks managing director Tay Tong said picture-taking "really depends on the circumstances".
For instance, if the production is in an auditorium or black box, the rule is that no photography is allowed as the sound and flashlight will mar the performance for the actors and audience.
"So we do discourage the practice and we will keep to this practice for a while despite the proliferation of social media," says Mr Tay, 49.
However, if the event is outdoors and is largely interactive and participatory, photography is encouraged. It was allowed during TheatreWorks' The Happiness Event held at Gardens by the Bay.
"It was one of our engagement programmes. Over 1,200 people attended and audiences encountered stories on Happiness by some 100 actors and the finale was a mass dance. For this participatory event in an open space, photography was no issue at all," said Mr Tay.
This relaxation of photography rules, some feel, is a good move as theatre productions are no longer simply a medium to express the artists' intent.
Productions facilitate audience expression as well. And that is where the ability to share socially plays a part.
Freelance public relations consultant Mansi Maheshwari, 27, a regular concertgoer, said more productions should encourage photo-taking as this makes for easier recall, sharing and discussion.
She emphasised that the practice must be incorporated in a way that it does not wreck the show for others. She feels the life and experience of a production is no longer limited to within the four walls of the theatre nor just the attendees.
"The production in this day and age is considered successful (or not) because of its ability to generate conversations outside of the theatre."
Last year, she attended the joint concert by Indian and Pakistani bands Indian Ocean and Strings as part of Kalaa Utsavam at the Esplanade.
"I remember Strings asking everyone to pull out their phones and so people took pictures and shared the content right after. That word of mouth lasted for a very long time. The audience shared clips on Facebook and people were talking about the concert long after it was over," she said.
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