Summary of the Example

    $ ROTATE CONTRAW CONTRAWROT      -- conventional orientation (CCD)
    $ IREVY  CONTRAWROT CONT
    $ ROTATE ARCRAW ARCRAWROT
    $ IREVY  ARCRAWROT ARC
    $ ROTATE OBJRAW OBJRAWROT
    $ IREVY  OBJRAWROT OBJ

    $ YSTRACT CONT 185 194 S         -- review of counts, widths and shapes
    $ SPLOT S RESET \
    $ IMAGE CONT HIGH=hhhh RESET \

    $ ICUR                           -- select points on orders
    $ SDIST CONT .                   -- track and fit orders

    Either ...

       $ ECHMASK SDIST . MASK        -- create mask
       $ MASKEXT OBJ MASK . OBJE     -- extract orders using mask
       $ MASKEXT ARC MASK . ARCE    

    Or ...

       $ CDIST OBJ . OBJC            -- straighten orders
       $ CDIST ARC . ARCC

       $ ECHSELECT OBJC . OBJE OBJK  -- extract orders
       $ ECHSELECT ARCC . ARCE ARCK


    End either.

    $ ECHARC ARCE .                  -- identify arc lines
    $ XCOPY OBJE ARCE OBJE           -- copy wavelength info to object

    $ SCRUNCH ARCE . ARCS            -- scrunch arc and object
    $ SCRUNCH OBJE . OBJS

    $ ECHMERGE ARCS . ARCL           -- merge orders
    $ ECHMERGE OBJS . OBJL