Last Modified: December 3, 2014
Camera and Lens Choice
What camera and lens are being used?
What are your cameras being mounted on?
Lens calibration and operation requires rigging the Intersense and Airtrack units to the camera.
The mounting of the Previzion tracking system on the camera requires a 15 mm or 19 mm matte box rail attachment, and can easily accommodate regular matte boxes and standard teleprompters .
Lens calibration requires access to the camera and lens so we can run the live video from the camera, which is focused on a special optical target through the Previzion system . The image of the target is captured 20 x for each zoom and focus distance, and that data is used to create a customer calibration file of that particular lens.
This calibration file enables the Previzion system to accurately map the entry pupil location and any lens distortion for all aspects of a particular lens. All calibration lens data is stored on a serial number bases as every lens is slightly different.
The lens calibration process usually takes about 30 minutes for a prime and anywhere between 90 to 220 minutes for a zoom. This information is stored in a lens look up file which is keyed by serial number so that data can follow the lens from camera to camera. To change lenses takes just a few seconds to change the lens calibration file in Previzion.
Reading Lens Position
The Prevision system requires that the zoom and focus information from the camera & lens combination is available in a digital format. Currently we can read from any of the following camera data sources:
- Preston FIZ Mark II and III lens controller
- C Motion Camin lens controller
- Fujinon ENG type lenses with a serial port
- Canon ENG type lenses with Digi Power on zoom and focus
More detailed information on each of these is available in the manual under the Documentation->Connections heading.
Which decks do you connect to to record takes?
How long is the distance from the camera’s shooting location (on stage) to the Previzion station?
The longest data tether we can support from camera to system is 300ft (91.44m) with standard data cables.
Longer runs (up to 1km) can be achieved with fiber optic transceiver units such as the Telecast Copperhead 3400.