Landscape photographers, stop wasting money! This one clever trick with ND and polarizers keeps your shots sharp—and your wallet happy.

Using a polarizing filter, the research team, which included Robert Antonucci and Omer Blaes, professors of physics at the University of California, Santa Barbara, isolated the light emitted by ...

This admits of much more rapid and easily controlled changes in the wave-lengths transmitted through the filter than was possible with earlier types.