There seems to be a growing misunderstanding in the loupe industry that “adjustable focus” means “adjustable working distance”. It doesn’t, that's just focuspocus.That is not opinion or marketing language. It is basic geometry.Prismatic deflection loupes are built around a fixed convergence angle between the left and right optical channels. Those optical axes are physically aligned to intersect at a specific point in space, which becomes the designed working distance. Read Mo