Bug Report Webcam issue (Logitech C920) double webcam?

[d0dUxDJ]

I'll try to keep this short. Basically, whenever I reboot my computer (that's how I reproduced the issue, at least), my C920 source doesn't work. Just for OBS obviously. As soon as I delete and re-check for sources, it works again. If I don't, and try to just apply changes to the source I set up before rebooting, the menu shows two of the cameras, a greyed out one and a selectable one. Notes: I always change the resolution and FPS so that may play a role in this. I will test for it.

Any ideas on how to make the source permanent? It's a pain. I don't think a logfile would help in this case, since it's not a performance issue. I could be wrong, and if so I will post one per request.

W7 64 bit, latest OBS studio. Tried with nothing else open but MBAM and MBAE (antimalware and antiexploit), strobelight (something for screen refresh rate), realtek audio drivers (which should have no effect).

EDIT: Without editing the scene, it appears to save the changes and not "bug out". Is there a way to make it keep changes? The default seems to be 4:3 640x480, I'd need it to be at least a 16:9 resolution to resize the scene to the correct size at least. Better if it could keep the changes on reboot when setting custom resolution and FPS.

EDIT2: The problem seems to be inconsistent. It hasn't popped up in the past 2 reboots, but it has just 20 minutes ago doing the same things.

I now have two logs, one where it works, one where it doesn't. The one where it worked is this post. I will post the other file as a new post because it won't let me post more than one.

 

[SumDim]

It maybe that OBS Studio is getting confused to exactly which C920 to associate with. That you have two of them that are of the same manufacturer and make may be the problem. It may well be that it doesn't go far enough to determine device uniqueness when it talks to the device (i.e. it thinks its talking to webcam #1 but its really webcam #2).

FWIW, I have a C920 and C922. They work perfectly fine when used in the same scene.

 

[d0dUxDJ]

It maybe that OBS Studio is getting confused to exactly which C920 to associate with. That you have two of them that are of the same manufacturer and make may be the problem. It may well be that it doesn't go far enough to determine device uniqueness when it talks to the device (i.e. it thinks its talking to webcam #1 but its really webcam #2).

FWIW, I have a C920 and C922. They work perfectly fine when used in the same scene.

Oh uhm, that would be great... if I actually had two webcams. I only have one though, the program seems to save wrong data about the C920, and upon rebooting, "new" data is encountered, so it shows the previously saved as "greyed out" and the new one as "active", although neither work until I delete and create a new source. Then it shows only one. Screenshot and logfile attached. Language of the screenshot is Italian but should be comprehensible.

 

[SumDim]

​

11:54:56.598: C920: Video configuration failed
11:55:49.813: C920: data.GetDevice failed
11:55:49.813: C920: Video configuration failed
11:55:52.113: C920: data.GetDevice failed
11:55:52.113: C920: Video configuration failed

First thing, go download the current webcam drivers from Logitech.
Get this from the Logitech Gaming Framework software.
Verify that the camera works with these new drivers by using their software.

Then, remove all webcam sources and shut down OBS and restart again.

Try these settings:

If those dont work, you got a faulty webcam, bad USB connector, bad USB port, USB header, USB hub, etc.

 

[d0dUxDJ]

I had LGS installed, I deleted it with revo uninstaller, cleaned remaining files, rebooted, now reinstalling. Probably rebooting in a sec. I will try what you described, but as I mentioned, is it possible for me to use a 16:9 resolution? I mean, it always worked with regular OBS back in the day with the same OS and webcam... I made my layouts for 16:9, that's the main reason.
I will still try that 4:3 res with the settings you provided, which seem pretty solid.

EDIT: After reinstalling, my webcam settings don't save (as in, the ones from the actual logitech driver). I used to use LWS, the webcam software, but I uninstalled that too to follow your steps. The camera remains visible in OBS, but since I have to re-set my exposure and saturation and stuff every single time, that basically offsets the benefit of not having to re-set the source itself. If I had to pick, I'd prefer re-setting the source rather than every webcam parameter lol. This is a mess. And for all I know, it could be one of the couple of lucky reboots that didn't mess up the source.

 

[SumDim]

Yes, you can use 16:9 resolutions. Just right click on the webcam source properties.
In the Resolution/FPS Type choose Custom
In Resolution set to your 16:9 resolution from the drop down or specify your own

If the settings are sticking, there is a synchronization/locking/read only/write kind of problem going on. Those are not easy to pinpoint.

If that's the case, I wouldn't set webcam properties from within OBS Studio by triggering the config video button to bring up Logitech's property interface. Rather, with OBS Studio NOT running, go into your Logitech Gaming Software and set the C920 settings for exposure and color intensity. Close LGS.

Run OBS Studio. Right click on the webcam source and click the Config video button. The settings should be the same.

I'm not having this problem. Maybe its because you are running as Windows administrator?

 

[d0dUxDJ]

Yes, you can use 16:9 resolutions. Just right click on the webcam source properties.
In the Resolution/FPS Type choose Custom
In Resolution set to your 16:9 resolution from the drop down or specify your own

If the settings are sticking, there is a synchronization/locking/read only/write kind of problem going on. Those are not easy to pinpoint.

If that's the case, I wouldn't set webcam properties from within OBS Studio by triggering the config video button to bring up Logitech's property interface. Rather, with OBS Studio NOT running, go into your Logitech Gaming Software and set the C920 settings for exposure and color intensity. Close LGS.

Run OBS Studio. Right click on the webcam source and click the Config video button. The settings should be the same.

I'm not having this problem. Maybe its because you are running as Windows administrator?

I don't know what it is, but settings don't seem to save. Closed OBS, opened LGS. Changed some settings around (notably, exposure to -5 to avoid the laggish video output). Clicked X to close after saving the changes, checked and closed it from the system tray too, opened OBS, settings are jumbled up. Notably, exposure is -4 for whatever reason (causing lag). I'm... stumped. What do you mean by "Maybe its because you are running as Windows administrator?", I mean, shouldn't that be a benefit?

 

[SumDim]

It is the only thing that I see in your system that is different than mine according to your log file.

Some special set of conditions are causing the behavior of different values after being saved.

For example, when I change the color intensity value in LGS, close it, and then open it again, the value is the same.

However, for exposure the behavior is different. In LGS, I first have to uncheck the Auto gain checkbox. I don't get an integer value reading. Only a slider (Why are you getting an integer value if you are supposed to be using the same LGS software?)

So when I slide the exposure setting all the way to the left and save in LGS, I then close LGS. I then open LGS again and it doesn't show exposure at my setting. Its slid to the right about 20%. This tells me that there are other settings that are being used that involves exposure that results it to be set to a different value to conform. Either that or its a bug in Logitech.

In both cases, there is nothing OBS Studio can do about it. Thus, its best to use the LGS interface to set C920 settings and don't go through the Config Video button on OBS. Set it in LGS, then close it. Then run OBS Studio to have it read the current values that should have been stored by C920 in the registry or config file.

 

[d0dUxDJ]

It is the only thing that I see in your system that is different than mine according to your log file.

Some special set of conditions are causing the behavior of different values after being saved.

For example, when I change the color intensity value in LGS, close it, and then open it again, the value is the same.

However, for exposure the behavior is different. In LGS, I first have to uncheck the Auto gain checkbox. I don't get an integer value reading. Only a slider (Why are you getting an integer value if you are supposed to be using the same LGS software?)

So when I slide the exposure setting all the way to the left and save in LGS, I then close LGS. I then open LGS again and it doesn't show exposure at my setting. Its slid to the right about 20%. This tells me that there are other settings that are being used that involves exposure that results it to be set to a different value to conform. Either that or its a bug in Logitech.

In both cases, there is nothing OBS Studio can do about it. Thus, its best to use the LGS interface to set C920 settings and don't go through the Config Video button on OBS. Set it in LGS, then close it. Then run OBS Studio to have it read the current values that should have been stored by C920 in the registry or config file.

I see what you are saying, but it does not work like that for me. Thankfully I found out that the correct method is not caring about LGS at all. I would show you what it looks like for me in LGS (numerical values for the things, e.g. my white balancing would be around 5500ish) but I'm scared it'd mess up the settings I'm using now.

Basically I downloaded LWS, the very old webcam software by Logitech, that is out just for a handful of cameras (C920 is one of them). That app has sliders, I set it just how I want it and closed it (from OBS settings). If I close OBS, or reboot my PC, nothing changes now. So I'll just stay away from LGS as much as I can to avoid that annoyance. Thanks for your time trying to help me!

This whole thing is very weird though. Logitech should get their shit together :D Yeah, I understand this is not an OBS issue now that I've fiddled with it enough. I guess they could add an "overwrite *brandhere* settings" button to make the changes system-wide and permanent or whatever, but that is probably a lot of work for something that they didn't cause. But still, a man can hope.