I'd like to know how to calculate the new focal length when using a lens adapter. Is there any formula?
To be more specific: I need to attach my old lens (four third) to new micro four third system with MMF-2 adapter.
Lens mount adapters increase the pool of available lenses we are able to mount on any particular camera body. Adapters are basically mechanical coupling devices; however, some also couple electrical communications as well. Unless the adapter incorporates optics, the optical properties of the adapted lens are not altered. In other words, the focal length of the adapted lens does not change.