Blue Iris UI3 only showing substream

Sqvirrel

n3wb
Aug 23, 2025
2
0
Norway
Hello!
Pretty new to Blue Iris, and my setup has been up for about 1 month with 5 cameras.

The problem is as follows:
When I watch all the cameras at the same time in UI3, only substream shows, all well and good.
When I doubleclick a camera to look at it fullscreen, it still shows me only the substream. I know this because the resolution is horrible and unchanged, no matter what streaming quality I select in the dropdown box. I can also verify this because when I fullscreen a camera, it still shows me only 10 fps (sub stream), and not 20fps (main stream).
In Blue Iris itself, when I fullscreen a camera, I can see it change from low-res to full-res after a second or so, so the problem is isolated only to UI3.
If I download a recorded file, it is full resolution.
I cloned one of the cameras, removed the substream, and then the main stream was sent over UI3, I got 20fps, and changing the streaming quality on the dropdown actually made a difference.

Any idea to why UI3 insists on only broadcasting the substream to its clients, even in solo view? I am happy to provide more setup details if needed.

Thanks
Sqvirrel
 
Pretty new to Blue Iris, and my setup has been up for about 1 month with 5 cameras.

The problem is as follows:
When I watch all the cameras at the same time in UI3, only substream shows, all well and good.
When I doubleclick a camera to look at it fullscreen, it still shows me only the substream. I know this because the resolution is horrible and unchanged, no matter what streaming quality I select in the dropdown box. I can also verify this because when I fullscreen a camera, it still shows me only 10 fps (sub stream), and not 20fps (main stream).
In Blue Iris itself, when I fullscreen a camera, I can see it change from low-res to full-res after a second or so, so the problem is isolated only to UI3.
If I download a recorded file, it is full resolution.
I cloned one of the cameras, removed the substream, and then the main stream was sent over UI3, I got 20fps, and changing the streaming quality on the dropdown actually made a difference.

Any idea to why UI3 insists on only broadcasting the substream to its clients, even in solo view? I am happy to provide more setup details if geometry dash lite needed.

Thanks
Sqvirrel
Hi Sqvirrel,
As your describe, this happens pretty often if the main stream isn’t being passed to UI3 correctly. One quick workaround (besides cloning like you did) is to go into the camera settings → Video → Configure… and double-check that the substream is marked properly. If UI3 can’t detect the main stream mapping, it’ll just stay on the substream even when fullscreen.
 
Thanks for answer!
Taking your advice, I started tinkering with the video settings. In Video -> [Image format] I had Size (resolution) set to the same resolution of the main stream. When I changed that setting to the resolution of the substream instead, it worked!
I have to admit, I dont really understand what the Size dropdown-box really does, but apparently it has to be set to the resolution of the substream instead of the mainstream...(?).
I still notice that I am only getting 10fps (substreamfps) when i solo view a camera in UI3, but at least I get the full resolution now, so I will settle with that (unless you point out some other obvious thing).

Regards!