When taking the MRT to work, we are probably too preoccupied with our thoughts to notice what other commuters are doing.
But photographer Edwin Koo has managed to capture these moments, providing a peek into how travelling can be for the thousands who have to deal with the peak-hour crush.
Mr Koo started taking the photos in 2011 when he returned to Singapore from Nepal after two years.
He said: "When I saw how crowded Singapore's trains had become, I started to photograph the situation out of a sense of frustration and alienation.
"I was protesting against the system. When my anger died down, I realised that there are interesting things I could observe from the frozen moments at the train doors.
"Each scene presented a glimpse into the Singapore we live in today."
This insight inspired a new collection of photographs he took from last October to this February.
These have been compiled into a photobook called Transit, which is part of a series called TwentyFifteen. It is project initiated by a group of local documentary photographers called Platform.sg.
Platform.sg is funding TwentyFifteen, which will see 20 photo books published.
The sales of Transit, which costs $25, will go towards funding the subsequent books in the series.
Mr Koo's book was launched on Tuesday, Apr 7, at the National Museum of Singapore.
He also uploaded the pictures on Facebook last Thursday.
Since the upload, 12 people have come forward asking for prints of the photos they were featured in.
Mr Koo said that he is also using the book launch as an opportunity to meet the people in the photos.
He said in his Facebook post: "I may have made some commuters uncomfortable, especially since I was unable to communicate to you the nature of this project.
"So now is the time for redemption..."
Ms Nadiah Laksamana is one of the commuters who were photographed by Mr Koo.
Her friend had alerted her to the photo when he tagged her on Facebook.
She said: "Even though it appears that I was looking at the camera, I wasn't aware that there was someone taking a picture of me."
And her reaction upon looking at the photo?
"Why is my face so black? I wasn't even sure it was me."
"I had to ask my sister to verify that I was the person in the photo," said Ms Nadiah.
Reaction online has been encouraging.
Mr Koo said: "Many strangers have shared the album with their friends just to help me locate the people in the photos.
"Of course, there were people who raised the issue of privacy. My intention was never to intrude on the privacy of any individual but to paint a collective portrait of the commuters in Singapore."
Mr Koo came to two broad conclusions after this project.
"First, contrary to popular perception, our mass rapid transit has improved tremendously over the last four years.
"In 2011, waiting time was longer and trains were generally more crowded. Now, the trains come more frequently and the platforms clear quickly even during peak hours."
The second thing he noted were small acts of kindness.
He said on some days, when negative reactions got him down, these acts kept him going.
"...Along came a smile or peace sign from a random commuter and that really made my day, even if it didn't make a photo," he said.
This article was first published on April 7, 2015.
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