| Feature | HDMI | SDI (3G) | SDI (12G) |
|---|---|---|---|
| Max Resolution | 4K60 (HDMI 2.0) | 1080p60 | 4K60 |
| Cable Length | Up to ~10m | Up to 100m+ | Up to 100m+ |
| Connector | Fragile, clips | BNC, locking | BNC, locking |
| Typical Use | Consumer cameras, PTZ, DSLR | Broadcast, ENG cameras | 4K broadcast |
| Audio | Up to 8ch embedded | Up to 16ch embedded | Up to 16ch embedded |
| Hot-plug safe | ⚠️ Can reset stream | ✅ Yes | ✅ Yes |
Choose HDMI if your cameras are consumer or prosumer — DSLRs, mirrorless cameras, PTZ cameras, camcorders, gaming consoles, laptops. HDMI is widely supported, cheap to cable, and perfectly suited for runs under 10 metres. For Zoom, Teams, OBS, vMix or university lecture capture, HDMI is almost always the right choice.
Choose SDI if you are working with broadcast cameras — news cameras, studio cameras, ENG cameras. SDI uses locking BNC connectors (no accidental disconnects during a live broadcast), supports cable runs over 100 metres, and is the industry standard for professional broadcast infrastructure. If your camera has a BNC output labelled "SDI", you need SDI capture.
Use our Product Selector — answer 7 questions about your camera and workflow, and we'll recommend the exact Magewell capture card.
Choose SDI when: your cameras or production equipment already use SDI; cable runs exceed 10 metres; you are working in a broadcast environment with existing SDI infrastructure; or you need the robustness of locking BNC connectors (unlike HDMI which can be accidentally disconnected). HDMI is the better choice for laptop, consumer camera, and prosumer device connections, and for shorter cable runs.
Yes. The Pro Capture AIO card accepts both HDMI and SDI inputs simultaneously on a single PCIe card. The Ultra Encode AIO also accepts both HDMI and SDI inputs and can encode from either or mix both (picture-in-picture or side-by-side). For mixed-format environments, these AIO products avoid needing separate cards for each input type.
Yes. SDI carries embedded audio alongside video — typically up to 16 channels of audio in the SDI stream. Magewell SDI capture devices extract the embedded audio for use in the host application. For SDI sources that do not carry embedded audio, Magewell cards with analogue audio inputs can capture audio separately.
Magewell supports SD-SDI (ST 259), HD-SDI (ST 292), 3G-SDI (ST 425 Levels A and B), 6G-SDI (ST 2081), and 12G-SDI (ST 2082) depending on the specific product. Entry-level Pro Capture SDI cards support up to 3G-SDI (1080p60). The Pro Capture SDI 4K Plus and 12G variants support up to 12G-SDI for 4K60. Check the spec sheet for your specific model.
SDI uses a coaxial BNC connector designed for broadcast environments — it locks in place, supports cable runs of 100m or more, and is the standard in professional video infrastructure. HDMI uses a consumer connector better suited for shorter runs and AV equipment. Both carry equivalent video quality at the same resolution.
Choose HDMI if your sources (cameras, laptops, mixers) use HDMI and your cable runs are under 10 metres. Choose SDI if you're in a broadcast environment, need long cable runs, or if your sources output SDI natively. Magewell also offers AIO models that accept both.
Yes, but it adds a conversion step and potential quality loss. It's cleaner to use a Magewell SDI capture card directly. However, if you already have SDI-to-HDMI converters in your signal chain, they work fine with Magewell HDMI capture cards.