Terry Richardson, Senior Instructor of Astronomy & Physics at the College of Charleston designed a "Make Your Own Safe Solar Viewer" for the upcoming solar eclipse and beyond. This set includes our L14810 achromat (52mm diameter by 600mm focal length) and a Barlow lens with a focal length of -27mm. For the achromat: Place the crown (double convex) with its strongest curve against the negative side of the flint. Use a couple pieces of masking tape on the edges to hold them together. The crown side faces the sky. Here are the college's links for instructions and additional information: http://richardsont.people.cofc.edu/safe_solar_folder/index.html
