Originally posted by John4287 There are two differences (major in my mind) between the K3 and the K5 series and these are: 1) the K3 uses two separate motors to operate the mirror and the shutter and 2) they added a damper to the mirror to reduce vibrations from the mirror going up. The K5 series uses only one motor and it is unclear to me if they had any type of damping on the mirror. Thus comparing the 2 cameras is apples and oranges. Using two separate motors I would think that a sensor of some sort is required to determine that the mirror is in it's fully up position before the shutter is allowed to operate. Otherwise you could be taking pictures with the mirror partially up. So with a low battery, the mirror motor might not have enough power to raise mirror (overcoming the additional effects of the damper as well), causing the mirror to return to the down position without triggering the shutter since the camera didn't sense the mirror fully up. Since the shutter wasn't triggered the camera could then cause the mirror to go up again, repeating the same scenario over and over. But other scenarios could be failure of sensor to detect fully up position or effects of continuous shooting causing the damping to increase beyond motor capability. I have yet to experience this issue but has anyone removed the lens to see what the mirror is actually doing? Is it going fully up and fully back down or is it oscillating somewhere in between the two positions?
That's a good question John. I never took the lens off to look at it. It sounded like it was going completely up and down, but that's only going by sound, which can be quite deceiving.
I will say that it was more common
for me to run into the issue with a battery closer to fully charged than near the end of its life. I didn't keep a log, but over time I felt like I was running into the issue more often within 30-40 minutes after putting a new battery in the camera. I'm not arguing it's not a power issue, just that I don't think it's related to the battery being low. Of course, the guy that ran into the issue with the AC Adaptor seems to confirm that, but of course, he's only one guy.
I do wonder about the damper, and if it may sometimes just cause the mirror not to complete it's cycle successfully. Other K-cameras, most notable the original K5, seem to have had some variant of the crazy mirror-flapping though, so I don't know how the two might be related. Whats interesting is that the K5-II/s doesn't seem to suffer from it at all.
Good info and points of inquiry!