Originally posted by JoseFF Scintilla, Please keep us posted on the evolution of your case. Very interesting
Thanks!
Thankfully, the AA Eneloops have been keeping the aperture problem at bay in the 3 weeks since my first post. The other night, my first shot out of the gate was black again (but only the first), and I discovered not too long afterwards that the Eneloops had run out, so it may be affected by battery charge. Switching back to a fresh D-Li109 at that point did not cause any black frames, but that was after a break of only a few minutes rather than a few hours.
Edited to add: As expected, shooting today with the D-Li109 (I forgot to put the Eneloops back in the bag) gave me nothing but dark frames unless using the aperture ring. What's more worrisome is that when I got back home and took the fully-recharged Eneloops right off the charger and popped them in, I
still got a dark frame, and it didn't open fully up to the proper aperture until about the fourth frame I shot (each one got progressively closer).
So the Eneloops are no longer hiding the problem completely like they were before, and the D-Li109 can only work the aperture block correctly if the Eneloops have primed it first.