Our USB camera very often (at least once every session!) gets stuck and cannot update the background.
Clicking the toolbar camera icon works… until it doesn’t. When stuck none of these things have any effect:
Clicking the camera toolbar icon
in “Camera Control” tab click “Update Overlay”
in “Camera Control” tab click dropdown, deselect camera and select it again
System info: Gweike Cloud Basic laser with Gweike’s USB fisheye camera connected with separate USB cable to Windows 10 PC. Lightburn 1.4 release.
In our experience this is the most reliable way to get the camera working again:
unplug camera USB cable
plug cable back again
open “devices” and click “ok”. This reconnects to the same device (the only device). After clicking “ok” the toolbar camera icon turns gray and then black again.
After that clicking the toolbar camera icon often works again, but sometimes repeating 1 2 3 is required.
The issue doesn’t seem related to any particular or unusual features used. It happens in mundane situations. For example, we can update the background image, arrange layers and objects, perform the laser job, open the lid, put new material in, then press the toolbar icon again to update background image … and the issue happens!
The camera appears to work without any issues as a webcam in Windows when LightBurn is closed.
Is there any further details or data (some type of log?) we can provide that could be of help investigating this issue?
How to elevate a forum topic to a support ticket or issue tracker?
The symptoms suggest the usual USB communications failure due to the usual imponderable causes.
I completely fixed a similar problem by replacing the camera cable with an identical cable from my Box o’ USB Stuff:
AFAICT, LightBurn uses the underlying USB drivers and, when they crash, LightBurn is unable to reset & restart.
Preventing USB glitches seems to be the only way to keep the rest of the video chain working, but that’s difficult given the lack of diagnostic traces from the OS.
Replacing the Usb cable with one that’s at least no worse may be a step in the right direction.
That’s useful input, thanks. In my tests so far with the camera outside of LightBurn the laser was always powered off. So I can’t rule out laser interference. Unfortunately the camera has a custom flat cable with a custom connector so I can’t immediately test with a different cable. But I’ll check for camera issues in other applications while the laser is running.
Another thought that pops up is if some DIY shielding for the camera cable could help, if the root cause is interference from the laser?
Part of the problem is that “other applications” use the camera in different ways, where a momentary loss of communication is no big deal and gets patched up on the fly without you noticing it.
If the problem is a poorly built cable, then no amount of deck chair rearrangement will prevent the ship from sinking.
With that said, make sure the connectors on each end have nice-looking pins with a good mechanical fit; slightly bent / poorly fitting pins have been the death of many a connection.
Yeah, possible. If camera issues appear also in other apps when the laser is running then that’s evidence for the interference hypothesis, while no such issues is still compatible with laser interference with the camera in lightburn only due to LightBurn being coded in some way that is extra interference sensitive. If the latter turns out to be the case then we could ask LightBurn devs to make less sensitive.