Originally posted by Ptitboul It is possible that all faulty lenses are "8 255".
I'm wondering whether it is possible to load the EEPROM data of such a lens, modify the lens ID data to 8 16, and then write back the modified EEPROM data.
The
same technique can be used to turn a (dual-drive) SDM lens into a screw-drive lens.
It is possible that it is only the lens ID of the offending Sigma lens that causes the K-1 to trip up (e.g., if it is used for indexing). In this case, the problem could be fixable without waiting for Sigma or Ricoh.
Finding the right place to modify in the lens ROM shouldn't be too hard by cross-checking the occurrence of fitting data values with other lenses (e.g. the comparable versions with a 8 16 ID).
Anyone up for some detective work? Happy to help, but we need the respective EEPROM data.
Last edited by Class A; 05-02-2016 at 04:01 PM.