First pull the lens hood
focus to to the minimum focus distance. This reveals three small
slotted screws. Remove and set aside.
Note the size of these compared to lens mount screws, don't drop one.
The built in lens hood
the optical block counter-clockwise (when viewing from the front). Then
the whole optical block simply lifts out as one
unit, very slick. Set aside somewhere safe as the elements are exposed.
If you need access to the center element it's done by unscrewing the
block in the middle, counter-clockwise.
Flip the outer casing
over and remove
three JIS lens mount screws & set lens mount aside.
Inside are two metal keys
helicoid. Remove the small JIS screws
for each key and set aside, paying attention to which key came from
which guide. Over years of use they work better where they are worn in
and can affect focusing if switched when installed.
Now we're to the point of
no return. Slowly
unscrew the inner focusing helicoid. Go slow while pulling
the inner helicoid away from the outer body with constant
pressure. It's very
to know where the focusing helicoid separates, because it needs to be
threated back on in the same exact spot or focusing will be off when