Evaporator Fin spacing Defrost

could someone point me in the right direction, regarding evaporator defrosting, mainly the fin spacing and effect on the defrost.
correct me if im wrong
the smaller the fin spacing, equals the more fins per inch, resulting in a greater surface area, and making frost build up easier due to the smaller gaps between the fins.
as a result the defrost period would have to be increased and the interval more often, the the same size evap with a bigger fin spacing and less fins per inch