Switch parts between two Zuiko 90/2 Macro lenses

Pontus · Expire: 2016-08-25

I'm lucky enough to have two Olympus Zuiko OM 90/2 Macro lenses. One has slightly scratched lens elements but is in great condition looking almost new. The other lens has perfect optics but is looking more used. I would like to turn one of the lenses into a user and the other one into an almost mint lens.

Switching the aperture ring would make a huge difference. Would this be something I can do myself (being relatively handy) without risking having small parts flying around the room never to be found again?

visualopsins · Expire: 2021-06-22

Leave $$$ lens to experienced professional would be my choice, maybe. Maybe not. Wink

I would use only the proper tools, stopping otherwise.

I would attempt to disassemble lens with stiff(?) aperture ring first -- fix the ring, get two working lenses. I know from experience removing aperture ring can make one or more ball bearings launch by tiny springs from little holes. Remove aperture ring with lens inside a clear plastic bag or tent with small holes cut for arms/hands -- the bag or tent does contain any launched balls and springs, and other falling parts.

Next I'd try removing optics from the lens with scratched optics, trading one element/group at a time with same element/group from lens with perfect optics. Typical is some elements/groups are easy to remove, others not so easy. Trading only the easy to remove parts may be enough to make one lens in great condition with perfect optics.

ZoneV · Expire: 2011-12-02

I would not reccomend mixing single lenses from several lens assemblies!
In some (older) lenses single lenses have tolerances too big to mix them and create a new lens with exactly the same quality.
Lens elements are measured exactly and paired together.
Read this in a Hasselblad "Forum" magazin interview with Zeiss member.

I think this is the reason why some lenses have on internal lens cells handwritten numbers.

Replacing the hole lens assembkly tube (with internalt tube) would be no problem, but opening this assembly could create a worse lens - not gurantee that it is worse, or one could realize without optical measurement it is worse.