The World's Currencies Like You've Never Seen Them Before

Some nations have debated getting rid of their smallest monetary denominations.

Even President Obama came out against the penny earlier this year.

Photographer Martin John Callanan is trying to save these coins for future generations, using images.

His project The Fundamental Units is a series of extremely large prints showing the lowest value coins from countries around the world. He hopes to photograph coins from 166 different countries.

The project is in collaboration with the UK's National Physical Laboratory, where Callanan is using what he calls "Europe's best microscope," an Alicona infinite focus 3D optical microscope to capture the images, according to Petapixel.

He takes 4,000 exposures, and then over three days he is able to process them into one single 1.2 x 1.2 meter photo.