How was mirror lockup problem with early P1/Mamiya 645 DF resolved?

[blumarble]

I just recently purchased a used Phase One DF camera.  And while it was on its way to me I discovered the mirror lockup problem that was occurring about 2011.  The last discussions seem to focus on the firmware as being the problem, and the last firmware version that still had issues was possibly v1.25(?).  It isn't clear to me whether that version or the next actually solved the problem.  However, the discussion suddenly seems to have disappeared, so I'm hoping it was because the problem was fixed.  My DF came with v1.25 installed.  I've been told that v1.59 is the current firmware.

Does anyone know if: a. it was a firmware upgrade that solved the problem, b. which version (did v1.25 do it, or was it a subsequent version?), and c. does anyone know of a "history" of firmware updates for the DF, the changes for each, and their dates (or some similar document)?  If 1.25 solved the problem, I might not need to, but still might update if there are other reasons to do so.

Thanks, Rob

[Alexey.Danilchenko]

I have Phase One DF with firmware v 1.59 - it does not exhibit the problem with Phase One P25+ at least.

Since I have reverse engineered Mamiya/Phase One camera<-->back protocol (did it to make Kodak ProBacks work on Phase One DF/DF+ bodies) - I can say that this mirror flapping stance and undefined state is entirely camera property (firmware).  What happens is that for certain messages when exchanging with backs (the messages sent when shutter is ready to fire) bodies starting with DF require a timed response. If that response window is missed then camera throws a tantrum (flaps the mirror and goes into undefined state). Rebooting the camera taking the battery out usually helps. Older bodies Mamiya AFD/AFD II behaved much more tolerably and simply waited for response for longer or simply went ahead with the action. Why the behavior in DF is implemented that way is beyond me.

[blumarble]

That's good to know.  I am also using mine with a P25+ back.  I think I'll try it for awhile and see if I get any lockups.  If I do, I'll send it to a dealer for the firmware update to 1.59.

Thanks Alexey,
Rob