Attach the lenses to the front of the webcam with electrical tape. Clean off any smudges made during this process.

Before assembling anything else, it's necessary to test out the webcam and take some measurements:

Get something from the bench like a “helping hands” rig or a vise to temporarily hold the webcam.

Point the camera straight down at the table a couple inches off the surface. Angle the desk lamp so it is lights up the table without casting a shadow of the webcam on it.

Download a copy of VLC media player:

http://www.videolan.org/vlc/index.html

With VLC running:

Go to menu Tools – Preferences

Click All under Show Settings

Click Input / Codes

Scroll down to the box labeled Live capture caching (ms). Change it to 0

Click Save

Now go to menu Media – Open Capture Device

Change the Video Device dropdown to your webcam

Change the Audio Device to none

Click the Advanced Options button

If you're using a 720p webcam change the aspect ratio from 4:3 to 16:9

Also check Device properties checkbox and click OK

Finally click Play

You should get a configuration box.

Uncheck anything that says auto.

Set Focus to 0 and knock Exposure down a few clicks.

When you click OK, you should get another box like this:

Change codecs until you get the framerate up as high as possible for the highest resolution.

Click Apply and OK.

With any luck the video feed should start! It will probably be upside down. To correct for this, click the Show Extended Settings button (has three vertical bars on it).

Go to Video Effects tab.

Go to Geometry tab

Check the Transform checkbox

Change the dropdown to 180 degrees and click Close

Now figure out what height the webcam will need to be at to focus on different things. Put a PCB under the camera and adjust the camera height until the image is in focus. Now measure the height from the lens to the board. How high is the camera when looking at a breakout board with no pin headers? What about a double-sided board with large components on one side? Establish a minimum and maximum distance and include some extra for oddball boards. This is the range that the height adjuster will need to travel.

Specifics of the actual construction are left to the readers' discretion. The adjustment dial is the only tricky part, referring to the diagram, it works like this:

The first nut is tightened down hard with a lock washer against the dial.

^-- This assembly goes through a hole in the top piece of wood.

The second nut is put on with just enough slack to allow the dial to turn.

The third nut is tightened hard against the second to keep it from unscrewing.

The fourth nut is built into the wood piece that the camera is attached to.

Also note the piece of cardboard stuck behind the moving block in contact with the stand. This helps take out the remaining slack and prevents the camera from wobbling as the height is adjusted.