Question / Help Man of constant sorrow... Multiple Webcam problems

[Dude McGee]

Hi, folks,

I'm experiencing massive trouble with my attempts to use more than two webcams. I have one Logitech C920, which almost never made any problems. Then I have two MS Lifecams, and using one is no problem at all. Together with the C920, that is.

But when I insert the second Lifecam, I get no picture in the configuration pane. After testing several USB ports it may happen, that suddenly the camera works fine, so that I have all three cams in three different scenes. But when I start the laptop again the next day, one Lifecam is missing again.

I wonder whether this is an OBS problem or a Lifecam problem. BTW: At the time being I use a Lenovo W510 laptop running under Win7 Enterprise. Patched to the brim. Working fine thus far.

Any help is appreciated! But -> I have already tested different external USB hubs, 2 and 3, I have tested all sockets the laptop offers. I have deleted scenes and configured the cams from scratch. There was no way to first figure out a determined way to get all three cams running, and second no way to save a session in a way that it worked before the computer was shut down, and worked again when it was fired up again.

Thanks so far,

Hartmut

 

[SimCitySimRacing]

I'm having a similar Problem I have two logitech web cams the C920 hd pro and the C922 Pro stream. In the past I have had no problem displaying both in the same scene at the same time and at whatever resolution I wanted but I just upgraded to a new pc and have a fresh copy of OBS Studio and just can't get them to display at the same time... Its ether one or the other... My windows, Logitech and OBS software are current with the updates. As far as the lifecams go not sure how new yours are but it was my understanding Win10 Did not support the older ones anymore.Hope someone can put some light on this subject. Thanks in Advance.

 

[SimCitySimRacing]

I'm having a similar Problem I have two logitech web cams the C920 hd pro and the C922 Pro stream. In the past I have had no problem displaying both in the same scene at the same time and at whatever resolution I wanted but I just upgraded to a new pc and have a fresh copy of OBS Studio and just can't get them to display at the same time... Its ether one or the other... My windows, Logitech and OBS software are current with the updates. As far as the lifecams go not sure how new yours are but it was my understanding Win10 Did not support the older ones anymore.Hope someone can put some light on this subject. Thanks in Advance.

Well I figured it out... I was running both off the same USB Hub Once I moved one to another Hub/port all is good now...

 

[Dude McGee]

I'm having a similar Problem I have two logitech web cams the C920 hd pro and the C922 Pro stream. In the past I have had no problem displaying both in the same scene at the same time and at whatever resolution I wanted

That's interesting since the Logitechs are different models indeed! My Lifecams are two older ones, about 4 years or so, and one from 2017. But the behavior is absolutely identical and afaik they are also physically identical. Seems as if OBs has a problem distinguishing between similar cameras. It's a pity that this forum is neither remarkably lively nor gets visited by the developers. At least it seems so.

But congratulations that it works for you now with two hubs. I had no success, I could connect each camera to a single dedicated hub and it wouldn't help either.

With respect to the Win10 support I can say that you can forget about the Lifecam software but the cameras themselves work fine.

 

[Caerdwyn]

Same problem here.Four cameras (2x C920, 1x C615, 1x C930). Everything worked in OBS Classic.

Symptoms: Green boxes or similar artifacting where camera windows should be, bluescreens (until OBS Studio 20).

Observations:
1. Logitech has not updated its drivers for the C920 since October 2012.
2. Bluescreens CANNOT originate in apps in Win10. They can only originate in the Windows kernel and kernel-space software (meaning: drivers. LOOKING AT YOU, LOGITECH)
3. OBS Studio made some changes around release 20 to improve performance. Apparently this has to do with how the data stream coming out of the drivers is addressed, and this triggered flaws in Logitech's driver.

Solutions:
1. One camera per USB head. USB ports occur in pairs, and on PC motherboards that usually means over-under pairs on the backplate of the motherboard, and for each pair of USB ports coming off of the expansion USB headers on the motherboard.
2. The above worked until Windows 10 build 1703, then it would only see one of the C920. Solution to THAT was to replace one of the C920 with a Microsoft LifeCam CinemaHD.

Problems still active (all of which can be traced back to Logitech's refusal to support Windows 10 properly):
1. Using the Logitech control panels to control color balance, gain, zoom, etc. work until the system is rebooted, then the settings are reset to default. Workaround (annoying) is to screenshot the settings once they are correct then manually set the control panels to
2. Sometimes (not always!) the control panel adjusts the wrong camera. Enumeration issue!

 

[lcaine]

Are you serious super annoying. I have 3 usb hub internal 2.0, 1 internal 3.0 and 1 pci 3.0 total of 12 usb

So I can't run 4 cans? I have 3 running great added the 4th 930e and says there are not enough resources
Computer is dedicated to video nothing else

 

[carlmmii]

When dealing with multiple USB webcams, you need to ensure that you're not requiring more USB bandwidth than your host controller can provide. There is a hard limit of 480mbps per controller for the USB2.0 spec, and for good connections that means you're lucky if you can get 2 webcams providing 1080p30 or 720p60 feeds.

The solution is always the same -- separate the webcams across multiple usb host controllers (use USBView to determine your topology), lower the resolution, or use a higher compression method for the webcam capture (MJPEG or H.264).