Alexa XT-Like CMOS Is Slightly Larger than 5-Perf 65mm; ARRI Repurposes Hasselblad Lenses to Match

Following the recent addition of UHD and 4K upscaling options for the Amira and Alexa, ARRI revealed the next stage of its high-resolution capture strategy with the announcement of the Alexa 65 camera system at the Cinec Munich trade show. Boasting a sensor that’s slightly larger than a five-perf 65mm film frame with open-gate resolution of 6560×3102, the Alexa 65 is described by ARRI as “a scaled-up version of an Alexa XT.”

Indeed, the design of the camera’s A3X CMOS sensor is said to be “exactly the same” as what is found in the Alexa XT—it has the same photosites, but many more of them—and the camera is described as being the same size and weight as an Alexa XT Studio. Initially, the camera’s frame rates will be limited to 20–27fps, but ARRI said it expects to expand that range early in 2015. The camera has four 4G-SDI outputs that can be used for monitoring. The Alexa 65 will work with existing Alexa XT accessories, and look file and CDL server support is the same.

Click image to see a higher-resolution version.

The decision to develop a large-format camera rather than simply make a 35mm-format Alexa with a higher-resolution imager indicates that, for now, ARRI believes the Alexa and Amira hold their own in feature films. (But who knows what we’ll see at NAB next year?) The Alexa 65 is positioned for use in image capture for VFX as well as the kind of event filmmaking that attracts cinematographers to 65mm and IMAX acquisition, even if they only use it for certain important shots and sequences from a given feature film. That’s another reason why it makes sense to use the same sensor technology found in the Alexa XT—footage from both cameras should intercut relatively seamlessly without any special effort in post.

It’s bound to be a niche, though. The first 65mm digital camera to market was actually the 4K Vision Research Phantom 65, which debuted way back in 2006. But that system has since been discontinued in favor of the Phantom Flex4K, which shoots at the same 4K resolution but with a downsized Super 35-format sensor.

From ARRI’s FAQ on the new camera, here’s a chart showing the size relationship between different shooting modes on the Alexa 65, traditional 65mm film in the ARRIFLEX 765, eight-perf 35mm VistaVision, and the Alexa XT. Notably, the Alexa 65 in open-gate mode offers roughly one-third more width compared to VistaVision.

Source: ARRI. Click image to see a higher-resolution version.

The size of a 65mm sensor poses a lensing challenge, which ARRI is addressing with a new line of eight Prime 65 lenses (ranging from 24mm–300mm) plus a single Zoom 65 with a focal range of 50–110mm. The new lenses use Hasselblad optics in an ARRI Rental-branded housing co-developed by ARRI and German lensmaker IB/E Optics. New focus, iris and zoom mechanisms have been developed, and the mount is a 64mm PL variant that ARRI is calling XPL. It supports LDS metadata, which makes lenses wirelessly controllable but, the company noted, can also be used to provide information to visual-effects artists working to match CG shots with live-action elements.

ARRI is also adapting lenses originally developed for the ARRIFLEX 765 to work with the Alexa 65 and its proprietary XPL mount and branding them Vintage 765. No word yet on any other lens-mount options, but ARRI said they may be added “in due course.”

Workflow will also require some heavy lifting, given the sheer quantity of data coming out of the camera — open-gate 6560×3102 footage will come screaming out of the Alexa 65 at a rate of 732 MB/second, or 2.6 TB/hour. Initial support is for ARRIRAW recording only (that means no ProRes).

A Codex recording engine similar to the one used in the Alexa XT is built into the Alexa 65, and existing Alexa XR Capture Drives will be able to record from the Alexa 65 at up to 24fps, Codex said. That gets you about 10 minutes of footage in open-gate mode on 512 GB media, but Codex said forthcoming Capture Drives will scale up to 2 TB of recording capacity for recording more than 45 minutes on a single drive, and up to 20 Gb/sec, enabling recording at higher frame rates.

Codex Vault Lab 65. Click image to see higher-resolution version.

A new Vault Lab 65 based on the existing Codex Vault S, with GPU processing and 8 TB solid-state Transfer Drives, will be able to hold around three hours of open-gate footage on set for playback, review, and color-correction, as well as recording duplicate copies for safe keeping. “Anyone familiar with ARRI Alexa and Codex Vault will be comfortable with the Vault Lab 65 workflow,” said Codex Managing Director Marc Dando in a prepared statement.

Dailies, editorial delivery, look creation, and LTO archiving can be handled by a near-set rack-mounted Codex Vault XL, with up to 24 processing cores. It can render open-gate footage “in near real time,” ARRI said, while simultaneously producing dailies “at speeds far greater than real time.” 

If you covet an Alexa 65 of your very own, you can forget about it for now. The Alexa 65 is being made available as a rental item only.