Hi,

We are working on a lab where students will use a reticle within the ocular of a stereoscope (i.e., dissecting scope).  The stage micrometers available are for compound microscopes.  Should I use a ruler?  We would like for students to measure below a mm, but if we calibrate using a ruler they will not be able to accurately measure anything smaller than a mm.  Any suggestions on what to purchase or use as an appropriate stage micrometer for a stereoscope?

thanks!