Ultimatte 12 with Alpha channel for offline projects?

I've been trying to find the answer to this question for quite some time. Can the Ultimatte 4K or 8K keyers save the keyed video video to a file and preserve the alpha channel? I do a lot of green screen work but take my keyed footage unto Unreal Engine and do my camera movement in Unreal Engine. So I need a great key but need it as a video file with an alpha channel. I'd LOVE to use something like Ultimatte 12, but don't know if it can do this? Is a live feed for a background image required? Or can I use it to simply key the footage and save it with an alpha channel?

There are two ways you can do this, I think. I am not sure about option #1.

The Ultimatte12 has no ability to save a file, you need to capture the output between the output of the Ultimatte12 and the input of Unreal Engine. Option 2 shows you my solution.

1) Can you bring in both the key and the matte into Unreal engine and then render out both files from there?

2) I am currently building a system where the key and matte will be saved to a Hyperdeck Studio 4k Pro. I plan on bringing in both of those into Aximmetry via the Blackmagic Decklink 8K card. The advantages I see with this system is that my keying will be completed prior to entering Unreal Engine and should the worst case scenario occur I will have a file copy of the key, matte and from the camera, the original uncompressed file footage. I have not gotten to the testing stage yet however I think I can take the matte from the Ultimatte and combine that with the uncompressed camera footage and come up with an end result what will be flawless. Should I need to go that far. Otherwise I'll just use the Ultimatte / Unreal footage.

Not sure if it will be of any use to you but LTT did a video about this a few days ago -

Have a look and it may provide you with some answers.

Not sure if it will be of any use to you but LTT did a video about this a few days ago -

Have a look and it may provide you with some answers.

Thanks. I saw that video, that's what got me looking into it again. I'd love to have the keying capability but cant use it for my offline workflow if I can't somehow save the video captured with an alpha channel instead of a background stream.

Does no one have an answer for this? I've been trying to get an answer to this question for almost a year. No response from BMD here or by phone.

Use two Hyperdeck's to capture the key and matte and then bring those files into Resolve. Use timecode when shooting to match the key, matte and unreal background to color correct.

Use two Hyperdeck's to capture the key and matte and then bring those files into Resolve. Use timecode when shooting to match the key, matte and unreal background to color correct.

Interesting. Is there any videos or documentation on this process where I can learn more?

Also wouldnt recording the key and matte in a capture card in a PC do the same thing?

Use two Hyperdeck's to capture the key and matte and then bring those files into Resolve. Use timecode when shooting to match the key, matte and unreal background to color correct.

Interesting. Is there any videos or documentation on this process where I can learn more?

I have not seen this online and I have not made any documentation for it yet. I do plan on it. Here is an image of my most recent test. I took a green screen video file from a job last year and played that out real time from Resolve through my UltraStudio 4K mini into the Ultimatte12. I recorded the matte to the hyperdeck and then brought that matte back into Resolve and use it to key my original camera footage. Note the file names on the clips. This gave me a great key without using any additional keying inside Resolve. I did have to apply a despill to the original footage however. This is because the matte is only good for the outside image.

Why would I do this? I wanted to have more creative control on the talent than I can get from the Ultimatte12 system. This allows me to grade the talent anyway I need to and also have foreground, matte and program files from the original shoot as well as go back into Resolve for creative grading if possible.

This same process is also undergoing testing on my virtual production system not only feeding different feeds into the system, but pulling those feeds, plus the Unreal Engine background out of the system. One I get my new computer system in it will have dual Decklink 8K Pro cards so I can feed in 4 feeds and pull out both program feeds as well as background feeds to the Hyperdecks.

Also wouldnt recording the key and matte in a capture card in a PC do the same thing?

It would. However you are asking your system to capture multiple feeds at, in my case, 4K. The Hyperdecks do this same thing as a dedicated capture device vs a computer needing to capture multiple 4K streams at once.

Use two Hyperdeck's to capture the key and matte and then bring those files into Resolve. Use timecode when shooting to match the key, matte and unreal background to color correct.

Interesting. Is there any videos or documentation on this process where I can learn more?

I have not seen this online and I have not made any documentation for it yet. I do plan on it. Here is an image of my most recent test. I took a green screen video file from a job last year and played that out real time from Resolve through my UltraStudio 4K mini into the Ultimatte12. I recorded the matte to the hyperdeck and then brought that matte back into Resolve and use it to key my original camera footage. Note the file names on the clips. This gave me a great key without using any additional keying inside Resolve. I did have to apply a despill to the original footage however. This is because the matte is only good for the outside image.

Why would I do this? I wanted to have more creative control on the talent than I can get from the Ultimatte12 system. This allows me to grade the talent anyway I need to and also have foreground, matte and program files from the original shoot as well as go back into Resolve for creative grading if possible.

This same process is also undergoing testing on my virtual production system not only feeding different feeds into the system, but pulling those feeds, plus the Unreal Engine background out of the system. One I get my new computer system in it will have dual Decklink 8K Pro cards so I can feed in 4 feeds and pull out both program feeds as well as background feeds to the Hyperdecks.

Also wouldnt recording the key and matte in a capture card in a PC do the same thing?

It would. However you are asking your system to capture multiple feeds at, in my case, 4K. The Hyperdecks do this same thing as a dedicated capture device vs a computer needing to capture multiple 4K streams at once.

Love it. I’m going to try this. Using the Ultimatte 12 will get me the quality of key I want, and doing it offline will allow me to send the footage into unreal engine and do moving shots in Unreal. Otherwise in doing live production my camera has to be locked off unless I want to get into massive complexities and cost of camera tracking and purchasing jibs and dollies. MUCH easier to do the slight movements in UE in post. But need the quality of keying I can get with Ultimate.

Keep us updated. Interested in your thoughts.

Keep us updated. Interested in your thoughts.

I will. I might have some more questions. Would it be possible to chat with you on the phone for a few minutes?

For example, I think one HyperDeck is for recording the black & white key from the Ultimatte, then do I need to record the green screen ftg on another HyperDeck or could I record on camera to CFast cards like normal?

I would be happy to MIchael, just drop me a message.

Regarding your question the image I posted above was the merging of an original camera file from months ago and the Ultimatte created matte recently created. One thing you need to make sure happens however is that the camera footage and the matte footage needs to be the same frame rate and resolution (size). There are a lot of options to capture a 4K image on the camera but only output a HD image via your SDI output. That would create issues when trying to match everything up.

Ok good to know. So the 12G SDI output from the 12K camera is only HD? Not 4K?

Ok good to know. So the 12G SDI output from the 12K camera is only HD? Not 4K?

Never mind. I see it does output 2160p60. But yes it makes sense they need to match. So if I recorded the same resolution on camera as the SDI output to the Ultimatte and hyper deck for the MATTE it would work?

Yes, that's exactly what I did.

Hello everyone,
has anyone found a way to record the keying result (i.e. only the talent) into one single file with alpha channel instead of into two separate files for key and fill? Ideally in 8k.

Best, Sven

Not with a Blackmagic product. The Ultimatte only outputs streams. You can do a key or a matte. The only way to combine them is to use the program...but that a single stream. There are no files generated. It's the same thing with the Hyperdecks...they capture single streams to single files. Even the Desktop video hardware and software cannot mix the files together.

For whatever its worth, I did eventually get a Ultimatte 12 keyer and a deck to record a key and fill. I found that the Ultimatte does not work well unless the green screen key is pretty perfect and lit well -- like in a studio. After experimenting I found I could get a better green screen key using Resolve's 3D Keyer and so decided to continue doing it that way and forego the Ultimatte system since I couldn't get it to get as good of a key.