What is the working distance of each microscope with and without supplementary lenses and any other accessory that is added to the bottom of the scope (i.e. image rotator or ringlight)? FAQ Report The effective working distance (link) data for each of the available Leica supplemental objectives can be found in the products section. The design of the new Leica StereoZoom® line allows ringlights to be attached directly to the microscope body and do not require any adapters so the impact on working distance is minimal.