It's not that straightforward. Clicking Source calls the DirectShow ShowCapFiltDialog() method on the in-memory instance of the selected cam's driver. The running driver code does "whatever that particular driver needs to do" to perform ShowCapFiltDialog(), which means "display your specific implementation of a Video Capture Filter Dialog". The details of how any particular driver implements this - or any other DShow method - are hidden inside the driver, by design and by Microsoft standards, for a number of good reasons. I can speculate that a Logitech driver probably keeps its DShow stuff in "lvuvc.sys" (or maybe "lvui2.dll") but I wouldn't bet on it since a Logitech driver install consists of about a half dozen dlls.

If I knew what you were trying to accomplish I might be able to provide a more useful answer.

>>>Simply wanted to adjust driver settings without having to go through AbelCam.

When I want to do that I use AmCap. I run AmCap, select the Logitech cam I want to work with, dismiss the "can't run preview graph" alert if it appears, and then go into Options -> Video Capture Filter to make my settings changes.

1) AmCap is a free MS utility that comes with the Platform SDK and also with some cameras. If you can't find a free copy easily I can send you one.

2) The "can't run preview graph" alert is a natural consequence of AmCap competing with AbelCam for use of the cam's video stream. Harmless but annoying. It can be avoided by un-checking Options -> Preview in AmCap. After you do that once it should stay un-checked on subsequent runs.

3) Settings changes you make this way will affect the stream going to AbelCam at once. Getting those changes permanently saved is another matter entirely - I make no promises there.