Remember Polychrome 12x magnifier we used to carry around to see whether we could see fine dots and see whether the shadow is still open? Jeff Jacobson recently found one. This was mainly for plates and there were higher magnification ones for film to see if the dots had a clear or fuzzy fringes. In the era of digital platemaking, film magnifiers are no longer needed but this magnifier for plates could still be in operation even today.
