Lens Data Options

Clicking the Lens drop down menu shows the current lens data acquisition options. Presently, these include:

  • Encoders (through the breakout box)
  • Fujinon serial data enabled lenses
  • Preston FI+Z/MDR lens control system
  • Pace Fusion
  • Panavision (through the Ethernet connection on the Panahub)
  • Manual (for manually specifying zoom and focus levels.)

Lens data is usually acquired through the RS232 serial link marked ”Lens” on the Previzion serial connector. In the case of the Panahub, lens data is acquired through the Ethernet port. When a lens data source is connected to Previzion and specified in the lens data drop down menu, the status light to the right will either light up green or yellow.

  • Green: the lens data connection is working, there is a calibration file loaded, and the min/max positions are set.
  • Yellow: the lens data connection is working, but either the calibration file or the lens min/max positions have not been set.


Encoder Min/Max Limits

Previzion’s lens calibration works by mapping the motion of the lens barrels as a floating point value from 0.0 to 1.0. Various lens systems handle setting the end points of the lens in different ways.

  • Breakout Box Lens Encoders: move zoom and focus lens rings to minimum position (wide angle/close focus) and click Minimum. Then, move zoom and focus lens rings to maximum position (telephoto/infinity focus) and click Maximum. A green light will appear by each setting.
  • Fujinon (ENG type lenses): these lenses use an internal potentiometer, which automatically sets Minimum and Maximum. Make sure to get the 16 bit encoding option, as the 12 bit encoding will produce noticeable focal length shaking.
  • Fujinon (Cine lens encoder): this lens encoder uses the same Fujinon serial data protocol as the ENG lenses, but uses encoders for higher precision and needs to have Minimum and Maximum set. Position the zoom and focus lens rings as described for the breakout box encoders, and click the Minimum and Maximum buttons at the proper distances.
  • Preston: the Preston MDR lens controller box automatically moves the lens motors to their minimum and maximum position when the motor is connected to the controller. If the lens data seems reversed, flip the lens direction switch on the MDR lens controller where the motor cable is attached.
  • Pace: the calibration is set at the camera.
  • Panavision: the calibration is set at the camera, by moving the lens to its near and far stops.
  • Manual: no minimum or maximum calibration necessary.

Click Close to close the lens configuration dialog when finished.