Displaying three USB video microscopes on a single monitor…

[chale44incolo]

Hi OBS gurus,

Severe newbie in your world, apologies in advance…so I’ve got three of those ubiquitous little Chinese USB video microscopes, that I want to display on a single good-sized monitor, all three “live” at once. How would I best go about this? Would the OBS software be appropriate? There’s no audio, no recording, just need to see all three scopes “live” while moving a very small thing around in their respective fields-of-view. What do you think here? I’d note this is a DIY at-home thing, so I’m trying to keep it cheap if I can. Thanks much—Charley in Lafayette CO USA

 

[murdocklawless]

install obs and check if obs sees these microscopes as a source? if not you can capture microscope windows as a source.

 

[chale44incolo]

Hi—thanks. I did install OBS, easy, and I’ve since been fiddling with the scopes this morning. I can get each of them (three of them, all different mfrs and models…) to show up as selectable sources, and my laptop’s built-in camera is selectable, too. I can get two of the three scopes, plus the laptop cam, to all three be video-active at once, cool. I don’t seem to be able to get the just the three scopes to be active at once; I fear one of the scopes is just too old and “1st gen” (it’s about five-six yrs old, the other two are much more recent) to be “happy”. So anyhow, clearly this IS gonna work for me, great!, with a bit more fiddling and I think replacing my “antique” scope with a new cheap guy. OBS is great, I’m impressed (and I know, using about one-jillionth of its capabilities!). Any other thoughts much appreciated. —

 

[AaronD]

So you have all but one working simultaneously in OBS? Does that one work by itself in OBS?

 

[chale44incolo]

Hi—yes, the older one <will> work in OBS, but when I then try to add the other (newer) two scopes, the older guy quits working…I’m just going to go ahead and get a duplicate of one of the newer guys, and I bet I’ll be ok. But, if you see any issues with how I’m going about this, I’d certainly appreciate hearing it. Thx—

 

[AaronD]

That'll probably work, though I've heard reports of *exact* clones causing problems because Windoze itself is stupid. USB is supposed to report a unique serial number for each device, but it's cheaper to burn the same number into every chip. Windoze, meanwhile, insists that everything follow the standard and is therefore optimized accordingly...

Compare that to Linux, which always looks at how the device reports itself, instead of caching the "correct" driver to use repeatedly, and is perfectly okay with multiple exact clones. It's just random what order they end up in, if they really are indistinguishable.

Depending on the quality that you're looking at, it could be a dirt cheap webcam shoved into it, in which case it might have that problem, or it might actually be something good, in which case it might not.

 

[JohnPee]

There is a potential issue when trying to get the three cameras working on your laptop and that is the internal bandwidth of the USB hubs. If you connect all three cameras on the same USB hub there may be a bandwidth issue. USBView will allow you to see what's connected to the USB ports and if you have the option to rearrange the connections. Have a look at the forum for a number of posts on USB connected cameras.

 

[chale44incolo]

JohnPee, thanks, I was meaning to mention the USB hub earlier. I’m using an “ONN” brand guy, “USB 3.0 Hub”, with a separate DC wall-wart power supply. It was a cheap basic unit, not really picked for this current purpose or anything. But it does have four ports on it. Do you reckon I need something different/better? I’ll look into USBView, don’t know it. And I’ll look into the forums further. Charley

 

[AaronD]

If they're all USB 2 devices, and everything upstream from them is USB 3, it's probably fine.

That includes not only the external hub, but any internal hubs and the host controller too. If any of that is USB 2, then you're trying to cram everything through a single USB 2 connection, and that can be a problem.

 

[chale44incolo]

Got it, I’ll look into that.