A useful add-on for the Andonstar microscope is a variable polariser filter. It is especially useful in making the text on some microchips visible as the text reacts to polarised light and by rotating the ring can be made more readable. In addition polarising filters can be added to the light source to get even more interesting results.

You will need to obtain a sheet of plastic polarising material (about £10 on Amazon, cheaper on eBay) and cut a circle of 20mm. This should be glued into the well in the base with the knobbly outer surface. Place the main tube onto this and then glue the ring on top to hold the ring in place.