Gabriel Lippmann

The length of exposure (one minute in sunlight) is still too long for the portrait. It was fifteen minutes when I first began my work. Progress may continue.

During exposure, interference takes place between the incident rays and those reflected by the mirror, with the formation of interference fringes half a wavelength distant from each other.

The problem of direct colour photography has been facing us since the turn of the last century.

You can't smear acrylics, you know, it dries too fast.

In the final analysis, it is your decision to make, but it doesn't move as fast as I'd like it to move.