Greetings,
At the outset of my first post here, I would like to thank the contributors here for the excellent information and perspective you have provided us for a long time. Late last year, we finally got a MF back; so now perhaps I can contribute a bit as well.
Our Aptus22 has an AFD mount and is on a Mamiya RZII with a Leaf adapter. I have seen reports of certain problems with Aptus backs on RZ's, but do not recall anything quite like what we have encountered.
We have recently spent a lot of time testing our Aptus trying to determine why it often shoots about two stops underexposed (whether daylight, strobe, or a combination). We finally stumbled on a consistent pattern of behavior.
Every time we turn on the Aptus (untethered) or connect it to the laptop, and do not change any settings as initially loaded, it starts shooting two stops underexposed. It continues to shoot two stops under until a setting has been changed at least once in the shoot setup menu (untethered, that means in the Camera settings; tethered, that means in the Shoot Setup menu in LC 8.4.6). Once a setting change has been made, the Aptus shoots all following exposures correctly, regardless of any further setting changes, until it is turned off or disconnected.
Initially, we thought the only setting change that triggered correct exposure was the Gray Balance setting. That was because if we set a custom gray balance to a dark capture while the Aptus was not tethered, that would then trigger correct exposures for all following shots. (But when tethered, setting a custom gray balance, and saving it, would not trigger correct exposures; only making a change in the Shoot Setup menu would trigger correct exposures.) On a whim, I tried changing the Color setting (Portrait Even to Portrait Even 5) after starting the Aptus and found that also would trigger correct exposures.
Based on all this, I am guessing that our Aptus is not loading properly when it is turned on or connected. Looking back, we think it has been this way since we first got it. (It has been updated with LC 8.4.6 since we got it; and as recommended, prior Leaf/Aptus software/etc. were cleaned from computers before the Update. We use LC 8 for tethering to our Titanium Powerbook G4; will go to LC 10 or 11 when we get a MacBook Pro.)
The good news is that this workaround works reliably for us and we get great files from the Aptus. Of course, we would rather not have to use a workaround.
I emailed this issue to Steve Hendrix (our dealer) and Rick at Leaf America. Steve responded that Rick had indicated that this was a known issue and being worked on by Leaf. I am posting this here and on the Ask Leaf forum in hopes it will be useful for others.