The researchers stumbled on the ultraviolet technique by accident, after spending four months mapping the frescoes as preparation for a possible future restoration.
In the course of the project, they found that by shining ultraviolet light on the paintings they were able to see much more than was visible to the naked eye.
The frescoes are thought to have been admired by Michelangelo and are said to have influenced his work nearly 200 years later.
The paintings were covered in whitewash in the 18th century and then underwent a brutal restoration in 1840, when the whitewash was removed with the aid of steel wool scrubbers and solvents. The work left the masterpieces faded, scratched and washed out.
Art lovers, however, are unlikely to see the enhanced paintings because permanently bathing them in ultraviolet would damage them.
Restorers hope instead to use the ultraviolet images to build a computer-generated facsimile of the chapel.