Purpose

With no arguments, print the current focus setting for the
LRIS blue dewar. With one argument, reset the blue dewar focus
to the specified value.

Usage

focusb [value]

Arguments

value = new dewar focus value [microns]

Output

The new/current focus setting is printed on stdout

Restrictions

- "value" must be a real number

Exit values

0 = normal completion
1 = wrong number of arguments

Example

1) show the current blue focus

focusb

2) change the blue focus to 2112

focusb 2112