What resolution have you set for the NDI output? There’s a very visible quality loss with NDI, especially in 1080p or lower. 

I set the definition of 2160X3840 for NDI.If I use the acquisition card, will it improve a lot?By the way, does Aximetry only support AJA on-board acquisition cards

What rendering resolution have you set in the project settings? There’s no point in a 4K output of you’re only rendering in 1080p.

Aximmetry supports Blackmagic Decklink cards as well, plus a few others I can’t remember. No sure how much the quality would improve in 4K. 

Did you try turning off Allow Virtuals in the Cameras panel? That should improve sharpness of the video billboard

THE  rendering resolution is 2160x4096.I installed the BMD acquisition card, but it was not recognized in the channel matrix.

This is my card.

 but it was not recognized in the channel matrix.

Which version of Aximmetry are you using? Have you updated to the latest Decklink drivers?

Broadcast 

It’s the latest drivers

Hi,

Do you see the capture card in the Video Outputs window?

By the way, I don't really see the quality difference between the two images in your first post. Other than that they were saved with different resolutions.

Warmest regards,

Thank for your answer.The  video ouput is 2160x3840.Actually,it's different.

Maybe it's because I use Tiktok to push the stream

Ah, so you’re monitoring what’s coming back from the streaming platform. That can of course be much lower quality, but that has nothing to do with NDI or Aximmetry. Even if you send 4K to TikTok that’s not the resolution the viewer will actually see.