 A reconciliation of all these disadvantages and advantages can be attained by a properly designed and operated universal ESEM.Concomitant with the limitation of useful specimen distance is the minimum magnification possible, since at very high pressure the distance becomes so small that the field of view is limited by the PLA1 size.In the very low magnification range of SEM, overlapping the upper magnification of a light microscope, the superior field is limited to a varying degree by the ESEM mode.