Let be a space (an object of a category of spaces), let be the category of sheaves on the frame of opens on , let denote the wide subcategory of with only étale morphisms. Then there is an adjoint equivalence
where
sends an étale morphism to the sheaf of local sections of .
sends a sheaf on to its espace étale.
We wish to clarify in which sense also the - topos can be regarded as an -sheaftopos on .