For loosening the ring and adjusting the position of the viewfinder 
to the left or right.
Viewfinder
TOP
Viewfinder Slide Lock Ring
Eyepiece Focus Ring
For adjusting the visibility.
Viewfinder Eyepiece Lock Ring
For loosening the ring and adjusting the eyepiece position of the viewfinder to the front or back.
Viewfinder
Eyepiece
Prevents external light from entering the viewfinder screen and cameraman’s vision.
