SEEK(OPCS)		Optical Printer Control System		SEEK(OPCS)

    NAME
	seek - seek to positions quickly on camera/projector(s)

    USAGE
	seek [pro2] [pro1] [cam]	# slew pro2, pro1 and camera 
	seek [pro1] [cam]		# slew pro1 and camera
	seek [cam]			# slew just the camera

	'-' can be used in place of arguments for motors that you do not
	want to change.

    EXAMPLES
	seek 3400             # slew 3400x on camera
	seek 3400 3400        # slew 3400x on both pro1 and cam
	seek >101             # camera seeks to x101 
	seek >100  >101       # pro1 to x100, camera to x101
	seek >1200 >55 >0     # pro2 to x1200, pro1 to x55, cam to x0
	seek >1200 - >34      # pro2 to x1200, pro1 unchanged, cam to x34

    DESCRIPTION
        SEEK is used to seek to certain frame positions at high speed. This
	command is not to be used for exposing film (see notes below).

	If SEEKCAP(OPCSDEFS) is set to 'yes', the fader will automatically
	cap whenever the SEEK command runs the camera. After winding, the
	fader will return to its previous position.

	SEEK ignores any FEED(OPCS) files in progress. This allows you to
	shuttle film around without interfering with motion control moves.

	SEEK allows a simple way to quickly seek to start positions. SEEK
	figures out the proper ratios to get all the motors to their positions
	as quickly as possible. When running the camera, the 'fastwind' speed
	is used (see SPD(OPCSDEFS)), instead of the current 'exposure' speed.

	SEEK can be used in place of:

	    pro2 >1000 pro1 >1200 cam >100

	..which will take a long time to run because it runs the motors 
	one at a time. The 'seek' equivalent would be:

	    seek >1000 >1200 >100

	Note the use of > to specify absolute frame positions. Without 
	it, frame numbers will be interpreted as a relative 'windoff' value,
	the same way the other OPCS commands work.

	If you want to ignore a particular motor, just specify a dash (-) as
	that motor's argument, and the motor will not be moved, e.g.:

            seek >1200 - >100
                       ^
                       Ignore 'projector' channel

	Normally, camera operators will want SEEKCAP(OPCSDEFS) enabled so the 
	fader automatically caps during a SEEK that involves camera motion
	to prevent exposing film.

        The shutter position before SEEK executes is preserved on completion.

    WARNINGS
	Do not use SEEK for exposing film, it's only for slewing.
	It is recommended SEEKCAP(OPCSDEFS) be enabled to avoid exposing
	film during seeks involving the camera.

	During a seek:
	   
	    > The camera runs at its slewing speed, NOT the exposure speed.
	    > The projectors will NOT run in sync with the camera [NOTE 1]
	    > The projectors may not run in sync with each other [NOTE 1]
	    > The state of the viewer is ignored [NOTE 2]
	    > Film buckles will be checked
	    > Any pending Fades, Dissolves, and Feeds will be unchanged
	    > Fader will cap to prevent exposure [NOTE 3]

        NOTE #1: If their slewing speeds and/or PPR(OPCSDEFS) are different
        NOTE #2: Assuming buckle and viewer are not wired together
	NOTE #3: If SEEKCAP(OPCSDEFS) has been configured.

    SEE ALSO
        SPD(OPCSDEFS)     - sets the normal and slew speeds for motors
        SEEKCAP(OPCSDEFS) - configure the fader to cap during SEEK commands
        PPR(OPCSDEFS)     - sets Pulses Per Revolution (PPR) for each channel
	MATH(DOCS)        - math expressions (for use in frame specifications)
	SYNTAX(OPCS)      - Online calculator and OPCS math expression syntax

    ORIGIN
	Gregory Ercolano, Los Feliz California  09/04/90