Magewell Pro Capture SDI 4K Plus

Professional 12G-SDI 4K Capture with Loop-Through

The Magewell Pro Capture SDI 4K Plus is a single-channel SDI capture card supporting the full range of SDI standards from SD-SDI through to 12G-SDI, which carries 4K at 60 frames per second in a single coaxial cable. It includes an SDI loop-through output on the card bracket, runs on a low-profile PCIe x4 card, and is rated for continuous 24/7 operation. At £771, it is the professional standard for single-channel SDI ingest in broadcast infrastructure working with 4K sources.

SDI Standards Supported

The Pro Capture SDI 4K Plus automatically detects and captures the full SDI signal hierarchy:

• SD-SDI: standard definition broadcast signals
• HD-SDI: HD signals up to 1080i/720p
• 3G-SDI: 1080p60 and dual-link HD in a single coaxial cable
• 6G-SDI: 4K at up to 30fps
• 12G-SDI: 4K at up to 60fps, the current professional broadcast standard for single-cable 4K transport

This range of backward compatibility means the card handles legacy SDI infrastructure and current 12G-SDI equipment within the same ingest chain, without requiring signal conversion upstream.

The SDI Loop-Through Output

The loop-through output passes the incoming SDI signal directly to a second BNC connector on the card bracket. This allows a single SDI feed to go simultaneously to the capture card and to another device: a broadcast monitor, a routing switcher, a second recorder, or any other SDI destination. In broadcast environments where signal routing is tightly managed, this removes the need for an additional distribution amplifier or router tap at the capture point. The loop-through carries the unprocessed source signal, keeping it clean for downstream use.

Who This Card Is For

• Broadcast engineers building 4K SDI ingest into production and playout servers
• Live production teams working with 12G-SDI cameras, routers, and vision mixers who need single-channel ingest with simultaneous monitoring
• Facilities transitioning from HD-SDI to 12G-SDI who need a single card that handles both during the migration period
• Archive and acquisition operations requiring reliable single-channel SDI ingest for 24/7 broadcast workflows

FPGA Processing and Continuous Operation

Signal processing is handled entirely in dedicated FPGA silicon. Colour space conversion, deinterlacing, and scaling happen on the card without consuming host CPU resources. The 24/7 rating is not a marketing designation: it reflects the thermal design and component specification of a card built for always-on broadcast ingest, not occasional use. In permanent broadcast infrastructure where a capture card must run without interruption across extended production cycles, this matters.

How It Compares to the Pro Capture Dual SDI 4K Plus

For single-channel 12G-SDI 4K ingest, the Pro Capture SDI 4K Plus is the efficient choice: one channel, one PCIe x4 slot, one loop-through. If two independent 4K SDI channels are required, the Pro Capture Dual SDI 4K Plus (£1,527) provides two fully independent 12G-SDI pipelines on a single PCIe x8 card, each with its own loop-through output, at roughly double the price.

Software Compatibility

Compatible with vMix, Wirecast, OBS Studio, Adobe Premiere Pro, and FFmpeg. Supported on Windows 10, Windows 11, and Windows Server; Linux kernel 3.x and above; and macOS 10.14 and later.

StreamKit and UK Purchasing

StreamKit is an authorised UK Magewell reseller. The Pro Capture SDI 4K Plus carries Magewell's three-year warranty and ships free to UK addresses. UK technical support is available for pre-sales specification advice and post-purchase queries.