Blackmagic Forum

I have a Decklink DUO that has 4 in puts switchable to 4 outputs. Great product.

I was able to connect 2 cameras and another 1080p source into OBS. I'd link to upgrade to get 2 4K cameras as inputs.

I ordered the 4K Pro and found it only had One input!?!?! even though it looked similar to the duo.
The 8K pro again looks similar some old doc showed 4 in/out switchable inputs updated docs look like the 4K Pro which once realistically one input in OBS.

I had to return the 4K Pro. I'm hoping the 8K pro isn't as brain dead.

What is the real answer. How many cameras can I connect to a Decklink 8K Pro and get 4K video input to OBS or another capture software?

Ultimately I want to connect 2 or 3 cameras and get them into something like OBS. Can any one decklink card do this?

I don't think the DeckLink 8K Pro has actually started shipping yet (at least I couldn't find any mention of this card in the DeckLink SDK documentation yet).

So all we have to go by is the online specifications and press release announcing the card:
https://www.blackmagicdesign.com/media/ ... 0171115-03

Judging from this information, it seems like the DeckLink 8K Pro only supports a single input and output channel. The bidirectional nature of the SDI connectors is used to capture at 8K60 using quad-link 12G SDI (in that case all 4 SDI ports would be configured as inputs, but still capturing a single video input stream). Similarly, the 4 SDI ports could all be configured as outputs, for playing out a single 8K60 video signal over quad-link 12G SDI.

Or, two of the SDI ports could be configured as inputs and two as outputs for capturing and playing out dual link SDI video signals (still only 1 input and 1 output channel).

The key word Blackmagic seems to use in describing the cards with multiple input and output channels (DeckLink Duo and DeckLink Quad) is independent. From the DeckLink Duo 2 description: "Featuring 4 independent 3G-SDI connections ..." or "DeckLink Quad 2 features 8 independent SDI capture and playback channels ..."

The description for the DeckLink 8K Pro says: "DeckLink 8K Pro features four quad link 12G-SDI connections ..." Nowhere is it mentioned that the card supports multiple independent channels, so I'm assuming it doesn't support this.

Hello Douglas. The 8K Pro has only one input like most of the cards. Multiple connectors are used for inputs or outputs that may require multiple connections for the single image. The only cards that have multiple independent inputs and outputs are the Decklink Duo and Decklink Quad.

Regards, Gary

Sorry in advance Gary but i'm going to be a bit Bitchy about this card and Marketing in general...

There seems to be a lot of Myst about this product.....
At the point of press release this picture came with it.

Implying that it could do 4x 12G in or out. Suggestive sayd it looks like you could config what is in and what is out.. Like a Quad 2 but then 4 channels 12G.

Now the website mentions something else.. UPDATE 11-7-2018:: The image on the website changed again is now Quad IN/OUT as it was at release time, at one point it was 2xin and 2x out..

Which implies more like the 4K pro (which had also 2 SDI in and 2 SDI out.. BUT! only 1 channel for capture.. Because the B input was only for 3D and Dual link.. Something that wasn't clear at all..

Text from the website::

The ultimate digital cinema capture card! DeckLink 8K Pro features four quad link 12G-SDI connections and works in all SD, HD, Ultra HD, 4K and 8K DCI frame sizes. You get support for 8 and 10-bit YUV 4:2:2, as well as 10 and 12-bit RGB 4:4:4 with full Rec. 2020 color. In addition, you can work at up to 60 frames per second in HD, 4K and 8K. The four 12G-SDI connections support 16 channels of embedded audio each, for a total of 64 channels. DeckLink 8K Pro is perfect for the next generation of high resolution, high frame rate and high dynamic range workflows!

Four Quadlink? Wait! it is 1x Quadlink or four connections to make a quadlink. four quadlink would mean 4x4 = 16 connectors guys..

16 channels of audio per channel to sum to 64 channels of audio.. So it does 4x 12G input... But here comes the catch.. Why would it be able to handle 4 quadrants of 4K(12G sdi) (making 8K possible) but not handle 4 channels of 12G-sdi from 4 cameras??
Is that due to in frame sync?
If i sync up all cameras.. Would i be able to run 4 channels 12G same framerate to the card and fool it to capture that as 8K?
So many fuzz and questions about this card..

Sorry to be a little bit "bitchy" about this specs of the card.. But it has all to do with the Myst BMD is keeping over the decklink range of products.. There is no clear statement like hey this can be done with this card. It is all to much suggestive writing of marketing to give the idea the card can do more then it does in real life.

I made indead the same mistake with the 4K pro. Finding out on the forum that it only supports 1 channel while the website was pretty clear about 2x 12G sdi..

The answer is in this thread: One in and one out at the same time, nothing more.

Xtreemtec wrote:Sorry in advance Gary but i'm going to be a bit Bitchy about this card and Marketing in general...

This is exactly why I was confused. Thanks for the excellent summary.

Seems like a live shot with 2 4K cameras/source active in OBS would take quite a bit of hardware at this time. Need two cards and having two 8-channel PCI slots probably using external PCI via thunderbolt3. Cha Ching.

Works great for 1080p w/ Decklink DUO. Except I'd like more detail.

For what it is worth, I used the DeckLLink duo to capture 2 greens screens, with 3 people on each. so 6 total people. Chopping each person out individually enabling to put all 6 into a virtual set. The set had multiple 'angles' where I "zoomed on" on individuals by scaling up the image of the individuals. The scaling caused artifact I'd like to solve.

My hope is two use 4K cameras to allow better detailed zoom ins while still outputting 1080p on the composite.

It's all good feedback. I will pass along the understandable confusion to Marketing.

Regards, Gary

xlax360 wrote:Seems like a live shot with 2 4K cameras/source active in OBS would take quite a bit of hardware at this time. Need two cards and having two 8-channel PCI slots probably using external PCI via thunderbolt3. Cha Ching.

I'm not sure why you need Thunderbolt? If you have two x8 slots, you should be able to fit two 8K Pro cards.

I suppose 4K24p won't be too bad (it's only 60% more than 1080p60, and multiple 1080p60 sources is no sweat), but many 4K60p sources end up being fairly taxing. You really want GPU processing for that.

Steinar H. Gunderson wrote:I'm not sure why you need Thunderbolt? If you have two x8 slots, you should be able to fit two 8K Pro cards.

I suppose 4K24p won't be too bad (it's only 60% more than 1080p60, and multiple 1080p60 sources is no sweat), but many 4K60p sources end up being fairly taxing. You really want GPU processing for that.

Good point believe it or not I was doing this with a Skull Canyon NUC with the Decklink Duo in an external PCI case. But that is not viable moving to 4K. (It is nice and portable though)

But you a very correct that set up was getting quite crushed on the GPU as it is.

Going to need a bigger boat.

This changed recently… with the latest firmware, the Decklink 8K Pro can seemingly do four 12G-SDI inputs/outputs at the same time. So it's like a 12G version of Duo 2, at a slightly higher price.