The Nikon D5100's dioptric correction (for eyeglass wearers) has a range from -1.7 to +0.7 diopter, adjusted via a slider on the right side of the viewfinder eyepiece housing. The viewfinder has ...

A diopter adjustment dial adjusts the focusing of the viewfinder optics to accommodate eyeglass wearers, and the viewfinder also has quite a high eyepoint (meaning you can see the full frame with ...