DeckLink 8K Limitations

Modified on Wed, Nov 29, 2023 at 9:55 AM

After some digging with Renewed Vision - If we're doing 12G SDI outputs from a Decklink 8k Pro it can In theory do:
12G 4k/59.94 - FILL
12G 4k/59.94 - KEY
12G 4k/59.94 - STAGE DISP

We found that there is a bandwith limitation for Thunderbolt port/cable itself at 40g / 4 lanes of PCIe - After some testing we landed at:
12G 4k/59.94 - FILL
12G 4k/59.94 - KEY
3G 1080p/59.94 - STAGE DISP

This ended up working well and providing smooth video playback on a Mac Studio.

Summing up limitations of Decklink 8k Pro:

Can only do:

FILL/KEY/STG DISP (Cannot do a 4th out no matter resolution on 8k with a key active)
FILL1, FILL2, FILL3, FILL 4
FILL1, KEY1, FILL2, KEY2

With Thunderbolt PCIe Enclosure (Sonnet SE I for example)

(2) 12G 4k/59.94 and (1) 3G 1080p/59.94

We didn't test doing (2) 4k/59.94 and (2) 3G 1080p/59.94 with (2) Keyed outputs

To get 3 or 4 12G 4k/59.94 outputs we would have to do (2) sonnets/cards (as long as the mac has multiple thunderbolt busses) or upgrade to a Mac Pro and put the Decklink directly in the computer PCIe slot

Decklink 8k Pro , Thunderbolt 3 , Thunderbolt 4