Fujifilm GFX100: Severe Autofocus Errors
I saw repeated autofocus errors I saw on my first shoot. For that, I had used out of date lens firmware on the Fujifilm GF 110mm f/2 R LM WR (camera firmware was up to date).
The firmware was not the issue, rather, the GFX100 has severe AF errors.
Today, seeking a workable solution to the autofocus flakiness I had observed, I set up a Siemens Star target looking to answer a simple question: could the Fujifilm GFX100 autofocus accurately in fully magnified Live View? My thinking was that at least perhaps in magnified Live View, I could count on using the AF-ON to deliver spot-on autofocus, rather than having to manually focus every time.
For this test both the Fujifilm camera and lens firmware were the very latest firmware (1.01 for the GFX100 and firmware 1.1 for the GF 110mm f/2).
Sadly, I am able to reproduce at least 25% of the time major AF errors, whether in magnified Live View or unmagnified. Over and over and over. Which will make it quite tedious to test the camera, since AF is unusable with its present high error rate. I hope Fujifilm can fix this issue quickly, and I’m ready to help them.
Protocol:
- Single shot AF or manual focus setting for AF (allows AF-ON to work), with small focus spot.
- Enter magnified Live View maximum or any magnification, or don’t magnify (doesn’t matter).
- Press AF-ON; observe, repeat.
The only reliable way to focus seems to be manual focus, and that’s not so easy because the resolution is high enough for the image to shake just by pressing on the camera in any way (IBIS off, beefy tripod with Burzinki ballhead ). Alternately, focus and refocus with AF-ON until the image looks optimal in magnified Live View, and then hope it really is. And pray that unstable lens focus doesn’t kick in, whether using AF or manual focus.
Below, the GFX100 indicates autofocus acquisition via the green dot confirmation and the corresponding beep. It is so badly out of focus that f/8 won’t save it.
Below, the image should look very sharp as shown (manual focus).