SINGAPORE - Dressed in a green camouflage uniform, with a beret on his head, humanities teacher Benjamin Tan stands before a classroom, with a whiteboard behind him.
Another photo shows the 38-year-old in his work outfit of a white shirt and grey pants - but this time, surrounded by a tangle of forest.
This photo set is one of 25 in an online photo album that has gone viral.
The personal project by full-time photographer Koh Sze Kiat, 31, portrays operationally ready national servicemen from Mr Koh's unit in army gear in their natural working habitat. He then juxtaposes these images with photos of the men in their occupational garb against the background that NSmen are familiar with - the forest.
Mr Koh, who started his own photography firm Oddinary Studios in 2010, told The Straits Times that he came up with the idea while he was serving reservist.
"We play two roles - we are always thinking about work when we are in camp, and when we are back in civilian life, we are thinking about the next in-camp training," he said. "We are always entwined between two entities - the army organisation and our civilian life."
The photo gallery he posted on Facebook portrays that juxtaposition by placing men from his unit in their natural work environments - a list that includes a hawkerpreneur, an architectural associate, an administrative executive, a contractor, as well as husbands and fathers.
The album, titled With Our Lives, has garnered more than 3,300 likes and 3,000 shares since he posted it on Friday (Feb 9).
"I would like to share this personal photo project to mark the end of my 10-year cycle as an NSman of 803 Singapore Infantry Regiment and in just a few days' time, we mark Total Defence Day (on Feb 15)," wrote Mr Koh.
"More importantly, it is a celebration of all of our citizen soldiers whose dual roles support a strong economy and military that cannot survive without the other."
Mr Koh told The Straits Times that there was inertia when he first approached his army mates for the project.
"At first, people were like - what's this for, what are you going to use it for. Only a few were willing, at first, but slowly, more caught on."
Once he takes the last photo set of his commanding officer in the coming weeks, the gallery will be complete, with 26 people featured.
Mr Koh said an exhibition may be in the pipeline, but he plans to make prints first. The prints will be compiled in a book that he plans to sell at below cost price (about $5 a book) to his army mates and their friends.
He said he has not been approached by the Ministry of Defence, but it has shared his album on Facebook.
Mr Koh said the response was "super overwhelming and humbling".
"It wasn't something I thought would really go viral, because it's really for myself and my peers," he said. "I just made the album public. It came as a surprise."