See if you can spot what's wrong in these photos of crowds

Screen Shot 2016 10 14 at 10.42.44 AMPelle Cass, ‘Selected People’What’s wrong with this picture?

You can look at a Pelle Cass photo for several moments before realising it doesn’t make sense.

See if you can spot what’s going on in this picture of people walking down the stairs:

Figured it out?

“Each person’s foot is hovering an inch or so above the next step,” Cass says by email. “The odds that 19 strangers would be caught at the same crucial instant in the same instantaneous photograph just before landing on the next step must be astronomically small.”

How does Cass do it? Calling himself a subversive trick photographer, the Boston artist takes hundreds of photos on a tripod in a single spot over about an hour. He then goes back to his studio and carefully selects content to include in a composite image.

“I don’t change a thing and I never move a figure or doctor a single Pixel,” he explains. “I simply decide what stays in and what’s left out.”

Photos in “Selected People” can show a perfect spectrum of colours, a collection of people raising their arms, or simply an arrangement the artist finds striking.

“I never pass up the chance to make a joke, visual or otherwise,” he adds.

Cass shared a set of photos from “Selected People,” including a few never seen before. See if you can spot what’s wrong.

'Esplanade I'

'Esplanade II'

'Esplanade III'

'Circle Greenway'

Need help? Cass writes: ''It's a spacial trick. The people around the central figure holding the balloon form a rough circle that isolates him.'

'Greenway Crosswalk I'

Cass explained this series in an interview with Vice: 'The first picture looks ordinary enough: people waiting to cross the street, looking off to the left. But it turns out that it's all men on one side, all women on the other.'

'Greenway Crosswalk II'

'(T)he second picture ... is made up from the same set of exposures covering an hour or so, which shows families holding hands,' Cass says. 'It's as if they procreated in the middle of the street.'

'Chestnut Hill Reservoir'

'Hawks from Under'

'High Line II'

'High Line III'

'High Line IV'

'High Line V'

'Bethesda Fountain I'

'Bethesda Fountain II'

'Bed of Tulips, Boston Public Garden'

'On Bridge, Boston Public Garden'

'Bridge, Boston Public Garden'

'Trinity Church'

'Faneuil Hall Crosswalk'

'From Prudential Footbridge'

'Emerson Park, Halloween'

'Boston Public Library I'

'Boston Public Library II'

'Larz Anderson Park'

'Cypress Field'

'Amory Park'

'Tree, Boston Public Garden'

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