Apparantly we have at work a hackerspace with 3D printer and the likes so I took the opportunity and printed the lens.stl focus tool posted here (thanks!). It works as advertised and I could focus for a distance of 2-3 inches. More than enough to inspect PCBs.
When I re-focus it to the 'normal' operation (e.g. factory setting), what object distance should I use? I would think that shorter than infinity will provide better range.
![](http://i.imgur.com/4yspWX3.jpg)
The tool inserted into the camera.
![](http://i.imgur.com/dmF7nsW.jpg)
The tool upside down on top the the camera. You can see the portion that engaged the lens holder.
![](http://i.imgur.com/8XXjmQw.jpg)
A close up of the tip. When tried to upload the stl file to an online 3D service I got an error message. As you can see there are gaps and irregularities in the printed part. Am not sure why. Might be a discontinuity in the 3D model.