14-140mm II … Lowlight refusal to trigger shutter

jeffharris wrote:

alcelc wrote:

on various bodies, the GF3, GX1, GX7 and now GX85. When AF been locked by half press and hold the shutter, the focus distance usually never change. We use the focus and recompose style so if your finding happens To me, 99% of my photo would be OOF.

I use the modern method and shift the focus point.

I use half-press for focus, too.

I am now out and when back home, shall take a test on how low light AF 14~140 mk-II can do on GX7/85. Shall report to you later.

I was just playing around and it was working when setting the camera to MF (with the dedicated switch). I activated Focus/Release Priority to Release and it worked.

So, it looks like the problem is solved, at least for now.

Glad to know you have your concerned solved.

But I think there must some misunderstanding there from various replies which pointed you to use Shutter Release Priority instead of Focus Priority.

Yes, Release Priority might work because the camera will fire no matter has any focus been locked. So a risk of mis focusing or totally blur image having nothing in focus. Under Focus Priority the camera will only fired when a focus been locked (the intended focus or not) so totally blur image could be avoided. It is under the condition that the camera must has locked a focus (the green spot and beep sound AF confirmation) when we half press the shutter and keep it until firing.

If you are in AFS (single shot), once the focus been locked and that locking was held (keep shutter half pressed), the camera will never attempt to check on the focus again when we fully release the shutter. That is the basic of "focus and recompose" style of shooting. All of the Panny cameras I used, starting from the first Panny digital camera LC5, a few bridges and the MILCs from G1 to GX85 all have the same behaviour.

I suppose what it could be happened only under AFC or AFF that the camera will ignore the initial focus locking and keep on adjusting the focus for whatsoever falling inside the focus box at the point you fire. A reason I rarely use these modes because I want 100% control on my focus point. Other than that, I think I need to look at all of the settings you used for further investigation.

Basically under AFS, single focus point, focus has been locked and be kept until firing, it should not be possible to have the sort of your problem as described.

As said, a test was just done in my darkest room (bathroom with a small shaded window and today is over casting). According to the light meter App of my phone, it was darker than 0ev (lowest the app of my phone can measure), 14-140 mk-II on GX85 can lock focus as always (AFS, Single Focus point in its smallest size at the center):

Focus locked on the soldier, recompose such that the focus box falled on the camera when shot. Lighting condition around 3ev (with a light on)

Same as above, focus locked on the soldier, focus box on the camera when shot. Lighting condition <0ev according to my Phone App. On the parameters used should be 0ev ~ -1ev.

If you need something darker, I can do it again in the evening.