in the quick of the moment

An article describing how astronauts took photos of the Earth from space shuttles in orbits says:‘They shot what interested them, whether by long-held private plan, on timely tips from the ground, or, like most photographers, in the quick of moment. ’

Then, what is the meaning of ‘in the quick of moment’, please?

It’s not a good phrase to use, but it could only mean ‘with an instant decision’. A better idiom would be ‘and with a split second’s decision.’ (They didn’t think hard in advance about the shot, they just saw the image they thought would be a good photo and took it immediately.)

To do something without thinking about it beforehand is said to be done ‘on the spur of the moment’.