Question / Help Display Capture Black Screen on iMac, but OK on MacBook Pro

[benonkoebsch]

Hey guys, complete newb here to both live streaming and OBS!

I'm pretty stoked on everything so far, but I have run into an error.

I was originally planning on streaming from my MacBook Pro, but quickly realised it was not powerful enough to handle a 1080 30fps stream (I'm not a gamer, so I don't require 60fps) and so I switched over to my iMac which is more specced up.

Now for the life of me I cannot find a resolution to the black screen of death when using Display Capture!

For the record, I am using a iPad Pro as second display via Duet and this worked flawlessly on my MacBook Pro, but here on the iMac it returns the black screen.

I can see the display in the drop down (see attached) and I have no problem running a browser on the screen through duet, however OBS will not see it!

I'm hoping someone can assist here as nearly all the resolutions for this I am finding are Windows related, no one seems to have a fix for Mac?

Any help?

 

[benonkoebsch]

Anyone? Would really like a resolve on this one!

 

[benonkoebsch]

Here's a video highlighting exactly the issue I am facing: https://youtu.be/w-vHJ6mNXV8

 

[Narcogen]

I think the problem is that there just isn't anyone else trying to combine Duet and OBS. I'm more surprised that it worked on the MacBook than that it doesn't on the iMac-- the reason might be some difference in the GPUs between the two units.

A similar issue was reported back on version 18 of OBS but also apparently found no solution.

https://obsproject.com/forum/threads/obs-studio-18-01-unusable-on-2nd-monitor.65807/

A Reddit comment seems to indicate others also have not been able to make this work:

https://www.reddit.com/r/obs/comments/73u1ab/small_side_monitor_to_monitor_obs/

Is there a reason why you're trying to run a 2nd display on the iPad and then capture THAT display instead of the main one?

 

[benonkoebsch]

Thanks Narcogen.

The reason I am not capturing my main display is because I want to avoid the "infinity" problems that occur when you capture the same display you are running OBS on.

It looks like it cannot be done tho :(

 

[Narcogen]

On MacOS this can be achieved by either disabling the preview and/or by moving all the necessary controls into floating palettes and minimizing the main window to the Dock.

You might be able to utilize the Duet's display as a fullscreen preview rather than capturing it, have you tried that?

 

[benonkoebsch]

Hmmm, I've not heard of that work-around before Narc. Can you explain a little further the disabling the preview part? I mean if I disable the preview I cannot "prepare" the things I want to share - so for my use case I would like to line up YT videos ready to switch scenes and play them with commentary etc etc. If I minimise the window to the dock I cannot navigate around it?

As for Duet Display and OBS, if I use any browser aside from Firefox it glitches out (tried Chrome and Opera both flicker to full white screen when you alt-tab off them and back to OBS).

 

[Narcogen]

Right click the preview window in OBS. Choose Fullscreen preview. Move that window to your Duet display. Now you can see what you're doing. Or else you can use the Multiview Windowed setting from the View menu, and put that window on your Duet display.

In OBS' View menu, choose the Unlock UI option. You can now undock all of OBS' palettes with controls (sources, scenes, controls) from the main window and try moving them to your Duet display as well.

So now you've got your main display as the one you're capturing, and the other has your preview window and the control palettes. You won't ever be capturing a screen that has a preview on it, so no hall of mirrors effect, and you don't need to capture the virtual display being driven on the iPad since OBS expects to have a hardware GPU available and I'm guessing the Duet setup doesn't.

That said, I've never used Duet so I don't know if the above will work either-- it may be that OBS won't like having any windows on that display either, but it's worth a shot.

 

[benonkoebsch]

Thanks so much for the tips Narc, unfortunately Duet isn't really playing well with any of those scenarios. It becomes laggy and flickering constantly.

I do have another option tho, I'm going to try a different approach and use a couple of old HDMI monitors I have laying around and see if I can achieve a similar thing with them in place of the iPad on Duet. (I say a couple because I want to dedicate one rotated 90° as a pop out chat window from YouTube and the other will be my capture display...)

Will update all when I know the outcome, but for the time being folks I would suggest Duet Display on the iMac for some reason operators very differently to the same use case on a MacBook Pro.

 

[Narcogen]

Any recent iMac should be able to drive at least one second display without major issue.

 

[benonkoebsch]

I've got one working sweet (the 90° one) and now I am waiting for a USB to HDMI cable to test the second.

Will keep you posted :)

 

[Narcogen]

That USB to HDMI is where you'll likely run into a problem, I suspect.. but I wish you luck!

 

[Torey Striffolino]

Hey there :)

I'm not using Duet but am having the same black screen issue with my Macbook Pro (also new).

What should I do?



Cheers

 

[Narcogen]

Write a new thread and post a log.

https://obsproject.com/forum/threads/include-a-log-file-if-you-have-a-problem-heres-how.16571/

 

[benonkoebsch]

Please don't start a new thread, keep this going as it's a HUGE issue with OBS and there are plenty of people with this error. I believe my video is helpful for others, so Torey, please keep this thread alive for everyone's sake!

 

[Narcogen]

There is no indication that his issue is the same as yours as he is not using Duet. There are relatively few users of OBS on the Macintosh platform, and even fewer that answer questions about it in this forum. There's no indication other than one vague symptom (black screen) that DOES affect many people (on multiple platforms) but many more people have no such issue. There's no indication that there's a single root cause for these, especially since you first reported the problem related to a use case OBS was conceivably not built for-- the use of an external non-video device as a virtual display.

Throwing a bunch of only coincidentally related complaints into a single thread is a great way to get people to decide to avoid a thread. A new thread about a new problem with steps to reproduce, specifications and a relevant log are a great way to get interest and response. It's a lot easier for someone later to post that seemingly separate issues are related than it is to pull apart a spaghetti thread of responses "I have the same problem" without any details.

 

[benonkoebsch]

No worries Narcogen, if you think that is the best way to come to a solution, all good! :)

 

[polloken]

I'm having this black screen issue when trying to run a 2 camera set up. It was working fine and now it's not. I bringing each source as a video capture device. One camera is working and now the other is not. Is this a computer issue? Is my Macbook Pro capable of handling 2 video capture sources at the sametime? I'm currently running the latest operating system ( Big Sur). I've tried going to system preference-securities/privacy and OBS is checked in screen recording, camera, microphone. I've tried deleting OBS and reinstalling. Nothing has worked.
Ideas???