Gemini twins record 4:4:4 and 3D

Convergent Design has announced a new uncompressed hard drive recorder/monitor. The Gemini 4:4:4 is a small, low power, lightweight unit that has two drive slots for 1.8-inch solid-state drives, allowing simultaneous backup recording or optional 3D.

The Gemini includes a 5-inch 800x480 24‐bit, 900:1 contrast LCD touch‐screen for monitoring and playback, with zoomable 1:1 pixel viewing, with user positioning via touch control, for fine focusing.

It doesn't replace Convergent Design's existing nanoFlash (which records to CF cards and now has an installed base of over 3,500), but its use of higher-speed drives enables Gemini to record 10‐bit 4:4:4 or 4:2:2 video in the main HD, 2K or 3G formats, including 1080 24p and 1080p 50/60, with up to 16‐channels of embedded audio and timecode (four channel audio initially, which will be expanded in a firmware update).

The 1080p 50/60 data has to be striped across both drives, while 4:4:4 is only supported in 1080p 23.98/24/25/29.97 and 2048x1080p 23.98/24. The DPX file format will be supported in a firmware update.

"Uncompressed is a lot of data, typically in the range of 125 to 150 megabytes per second [1 to 1.2Gbps]. But, technology advancements now make full uncompressed workflow quite manageable and affordable," explained Convergent Design President, Mike Schell. "For example, using the new 10Gbps Thunderbolt technology from Apple/Intel, it is now very reasonable to edit uncompressed using a laptop. New $180, 3-Terabyte hard disk drives enable portable RAID arrays with 9-12TB of storage (sufficient for 18-24 hours of uncompressed 1080p24 4:2:2 10-bit)."

Having two removable solid‐state drives allows it to offer instant backups, to counter the risk of lost footage, or longer record times from recording on one drive after the other. It also opens up new workflow options. Gemini includes S‐Log and C-Log video support, with user programmable viewing look-up tables, which can be enabled selectively for either HD‐SDI output. This means that users could record native S‐Log to one SSD (for on‐line editing) and the same footage with burned‐in LUTs to the second SSD (for faster creation of offline proxies and/or H.264 video for mobile or web viewing).

An extra‐cost 3D stereographic option will also be available, enabling dual‐stream recording and playback in a single Gemini unit; creating what is claimed to be "the world’s smallest, lowest power, 3D recorder."

Gemini will record independent left/right channel files while providing full synchronized playback of two streams as well as side‐by‐side, 50/50 composite, or anaglyph combinations. "Gemini uniquely allows you to simultaneously view 3D video in multiple formats, such as side by side and 50/50 composite, which should be very helpful in 3D camera alignment," he added.

It is housed in a lightweight (450g), milled aluminium case, and is about the same size and weight as the popular SmallHD DP6 monitor, but includes recording, playback, image processing, dual HD/3G SDI I/Os, HDMI output and consumer level audio I/O; while consuming only eight to 15 Watts of power.

Planned future enhancements include reference image overlay (onion skinning), where users can capture still frames or create their own reference images (custom grid overlays, for example) to mix with live video, using an opacity slider. This will enable directors to check the current on‐set environment against a previous day’s production, assisting in camera setup and easily identifying anything out of place. Other features include: user-programmable over/under crank, time lapse, 3:2 and 2:2 pull-down removal, and on-screen tally.

Convergent plans to support all major NLE programs, including Avid, Final Cut Pro, Premiere, Vegas and Edius. Editors have the option to edit full uncompressed video (transfer time off the SSD to a fast hard drive is about 1/3 real time) or use any of the popular codecs (ProRes, DNxHD, Cineform, etc). For example, using a recent eight-core MacPro, the transfer from the SSD and software encode to ProRes, occurs in about half real time (60 minutes of video requires 30 minutes to transfer and encode – a simple transfer of the same footage would only be about 10 minutes faster).

"We found that oftentimes the workflow and editing system is not well defined at the beginning of a production, or the client may want the footage in a different codec or format. Gemini gives you the flexibility to deliver accordingly, at the best possible quality levels. So after two weeks of shooting, when the director brings word that you’re changing from PC to Mac (or vice versa), you’re ready to encode that pristine uncompressed footage into a new codec / format, while maintaining the highest possible quality," said Schell.

The requirement for greater throughput meant Convergent had to switch from Compact Flash to SSD. "Compact Flash is a great choice for most compressed recorders, but it simply lacks the required performance for uncompressed video. Compact Flash tops out at about 90MBps, while uncompressed video ranges from 100 to over 300MBps so, clearly, it’s impossible to record uncompressed video onto a single CF card. Additionally, CF card capacity maxes out at 128GB, while SSDs are now available up to 512GB," he explained.

The Gemini SSDs provide read/write speeds of 415/260MBps respectively. "For most video formats, a single SSD has a sufficient bandwidth; however, 1080p 50/60 formats generate over 300MBps, requiring us to strip the data across both drives. We do, however, combine the data into a single file during the offload of the SSDs to your Mac or PC." The drives have a 6Gbps SATA interface.


3D nano - Convergent Design from UrbanFox.TV on Vimeo.

Gemini won't replace the nanoFlash, which "will continue to find applications needing long record times (10 hours), and/or requiring a strictly compressed workflow. At $1 per minute [at 50Mbps] for the Compact Flash media, nanoFlash still offers the lowest media cost for broadcast quality video."

Most of the nanoFlash features, with the exception of pre-record buffer, should be enabled for Gemini when it ships. "That said, we anticipated many special requests, so Gemini was designed with five times the programmable logic compared to nanoFlash, giving us quite a bit of room to grow (feature-wise, that is)," added Schell.

The Gemini 4:4:4 Kit, which includes the recorder, 1.8-inch SSD to eSATA transfer station, AC power supply and cables, housed in a custom‐fitted hard plastic case, will cost $5,995. The 1.8-inch 256GB and 512GB SSD drive prices will be announced at NAB, where Convergent will demonstrate Gemini 4:4:4 on a Sony F3 and on a 3D mirror rig.

Related post: Convergent Design Odyssey7 + 7Q

By David Fox