Question / Help Does base res have to be 4K for output res to be true 4K, when using a 4K USB cam

[ansari56]

Hi! Thanks in advance for any help here.

All of this is using the Logitech BRIO (USB) 4K webcam..

I've never been able to figure out if the "base" resolution in OBS (presumably the resolution of the desktop monitor and supporting graphics card) needs to be 4K/UHD if I want to output 4K/USD ("output" resolution = 4K/UHD). OBS *does* seem to work (4K stream as reported by the streaming server) with the OBS "base" resolution set to 1080p (1080p monitor and 1080p graphics card), but the OBS "output" resolution set to 4K or UHD, while using the 4K USB webcam. On one hand, I assume this works OK since the webcam (Brio) is 4K, to have OBS output 4K ("output" res = 4K) to the streaming server, even though the desktop monitor and graphics card are 1080p ("base" res = 1080p). BUT LATELY.... I'm thinking that maybe OBS is just padding frames to "fake" 4K if the base resolution is 1080p, even if the camera is 4K, if that "base" resolution is not also 4K.

So... does someone know for sure? If already asked and answered (surely it must be somewhere on here already) please just give me a link. :) To summarize: "If I'm using a 4K camera, the logitech brio, and wish output 4K to a streaming server capable of accepting 4K, does my OBS "base" resolution (PC monitor and graphics card) need to be 4K, or will OBS output 4K properly (OBS "output" resolution) even if the base resolution (PC monitor and graphics card) is set to 1080p".

Thanks for the help!

 

[DEDRICK]

If you do not intend to capture your desktop or game running at 1080p then set your base and output to 3840x2160, the resolution of your webcam.

By setting your base to 1080p you are downscaling the 4K webcam to fit the 1080p canvas, which is fine, ...but then you are upscaling the output to 4K which will look terrible.

Pick one

Set the cam, base and output to 4K, don't capture your desktop or know that you will need to upscale it to make it fit the canvas.
Downscale the cam source from 4K to fit 1080p canvas (Ctrl+F), Output 1080p
Set the cam to 1080p, base/output 1080p (Recommended, running a 4K webcam is not easy)

 

[ansari56]

Ah, OK, I think I understand. So given the goal of "pass-through" 4K video from the 4K webcam to the OBS output to a 4K streaming server, the "base" resolution in OBS can be set to 4K, even though the monitor and graphics card are 1080p, since no desktop capture or gaming stuff is involved. Yes, I had forgotten about the canvas size issue here too. Hmmm.... Is kind of sounding like the easiest thing is just stay all 4K - 4K monitor and matching 4K graphics card.