On the side of some ZEISS lenses is a 4-pin LEMO connector, built in, with the words “eXtended Data” inscribed above it. This connector is part of ZEISS’s eXtended Data Technology (XD), which provides lens data for VFX applications. More specifically, eXtended Data efficiently transfers shading and distortion data via a hardware/software workflow. It allows VFX artists to adjust shading and distortion characteristics precisely in post-production. The compatible ZEISS lenses include the Supreme Prime series and the CP.3 XD line.
Ultimately, the lens data ends up in a software such as the widely used Pomfort Silverstack. In the software, attributes such as distortion zoom, distortion amount, and shading amount can be adjusted and fine-tuned to fit the VFX goals of the project. But there are a few ways to get the lens data into the software.
One way is via a MasterLockit timecode device, made by Ambient Recording. The lens connects to the MasterLockit over a LEMO cable, and the MasterLockit links up to your software over Wi-Fi. The lens data then flows from the lens to the software in a real-time workflow.
Perhaps the simplest way is to use a Transvideo StarliteHD-m. This is an on-camera monitor that records the lens data to an SD card, hence the simplicity. The SD card can then be offloaded to your software at a later time.
Another option is to export the data directly to a supporting camera, such as the RED DSMC2 (with firmware version 7.1 and above). The camera records the lens data on the video file, and the data can be extracted from the video in post-production and adjusted as needed.
No matter which hardware option is used, the lens data is generated in the software in a .zlcf file (ZEISS lens correction file). This file type is recognized in various other types of software, as well, such as DaVinci Resolve, so after all the distortion and shading adjustments are made, the file can be exported to these other applications to apply color correction and effects to the adjusted image.
eXtended Data Technology provides an alternative to the old way of making adjustments, which involved physically measuring focus distance and shooting grids and gray cards. The technology is based on the similar Cooke /i* data technology but additionally provides frame-accurate information about distortion and shading characteristics. (Because it uses Cooke /i* technology, virtually all hardware compatible with Cooke i/* can be used with eXtended Data. All cameras that record Cooke i/* data will record at least some of the ZEISS eXtended Data. These include all ARRI cameras, the RED DSMC2, and the Sony Venice. They’ll record information such as focus distance, iris, and pupil position, and this information can be used for seamless lens swaps, script continuity, tracking, and more. The data can also be sent to certain motorized follow focus units, such as those from cmotion. The follow focus reads the data and lets you see the focus distances and iris on your gear.
ZEISS Supreme Prime lenses are the second series to be designed with eXtended Data Technology. The original CP.3 lenses don’t have the eXtended Data LEMO port, while the CP.3 XD line is an upgraded version. Likely, more lenses with eXtended Data will be released, because this technology also provides other on-set benefits, such as lenses instantly being recognized by a camera instead of having to be selected from the camera’s database. This benefit certainly speeds things up for the camera operator or assistant.
The Supreme Prime and CP.3 XD lenses are available at B&H in close to a dozen focal lengths each. The companion eXtended Data hardware and software are available, too. Check out the B&H website or stop in at the B&H SuperStore today! Comment below!