Originally posted by Wheatfield Just an FYI: The K mount is an open source mount. Anyone can build K mount lenses without paying royalties.
If the third party manufacturers aren't making K mount lenses it's because they have made a business decision not to, not because Ricoh isn't letting them do it.
Originally posted by BarneyL AFAIK this only applies to the earliest version of the mount.
I don't think you can go get the interface control document including the data transfer protocols, as you would be able to with a fully open sourced item. They physical, mechanical mount may be open sourced, but not all of KAF2, 3, 4. I know I've seen references to Sigma reverse engineering the protocols for their autofocus K-mount lenses, and speculation that's why lenses like the 18-35mm have some focusing issues.