A Centering Camera for LinuxCNC

My old edge finder was wearing out and the "kick-over" was becoming "mushy". I thought a microscope might be a better way to pick up the edges of parts. I got a "SuperEyes" USB microscope on eBay, this is 11mm diameter and about 5" long. I made an aluminum tube that fit in a 3/4" end mill holder to hold and protect the microscope. It has setscrews to center the microscope to the axis of spindle rotation, and a slot that runs up the bore of the end mill holder to pass the USB cable out.

The camera runs all the way up inside the end mill holder, then the USB cord folds over and comes back down the slot in the shank of the adapter.

Here's the case I made to protect the camera and prevent the alignment from getting knocked off-center.

Here's what you see on LinuxCNC's Axis GUI screen when the "Camera" tab is clicked. I had to make some mods to the camunits software package to add a "crop" operation that performs a zoom function by cropping away the edges of the original image from the camera. With it zoomed in, and the camera set for a very close focus of about .2", I can easily see movements of .0001". The camera image shows the corner of my vise jaw. There IS a horizontal line in the crosshair of the image that is plainly visible on screen, but it is not clear in this image.