Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
The Step Down target is shown with uniform surface (top) and textured surface (bottom), in high resolution (left) and with digital approximations of mild blur (middle); and severe blur (right). The masking of the L-junction by the texture contours is more pronounced for the severe blur.
