FUJIFILM released the firmware 4.0 a few days ago, including some bug fixes and the latest film simulation, REALA ACE. But does it fix the issue that a lot of users have complained about - the Autofocus errors that have been introduced in the previous firmware.

FUJIFILM X-T5 Firmware release notes

Here is what the new firmware contains:

New mode for film simulation
A new “REALA ACE” mode is added that combines faithful color reproduction with crisp tonal gradations and is suitable for all kinds of subjects and situations.
The camera focuses on different subject in the face frame even though AF is detecting the pupil.
When the shutter button is half-pressed at the same time as the “AF ILLUMINATOR” light metering operation, the camera freezes in rare cases.
The camera freezes in rare cases while recording movie with an external monitor connected under the following conditions.

［Setting conditions］
・MOVIE MODE: 4K 16：9/59.94P
・MEDIA REC SETTING: H.264/422 MOV
・IS MODE (MOVIE): IBIS/OIS+DIS
・HDMI OUTPUT SETTING: HDMI OUTPUT INFO DISPLAY ON

A minor bug.

FUJIFILM X-T5 Firmware v3.01 Autofocus issues

The Firmware 3.01 introduced a few issues in the autofocus area. After upgrading, I did notice a higher rate of hunting from camera, especially in situations where the subject (typically humans in my applications) were near flowers. Once the camera would lose focus, it will stick to the other subjects it would detect and stay on it.

On video as well, the camera would tend to detect random subjects and stick to them in stead of focusing on the main one. Even if a face was detected, it would still tend to detect random faces in the frame from time to time, which would throw the focus off. And it would take time to recover.

And finally, I would tend to have a lot of false positives. The green marker would tell me that the eyes are in focus but a lot of shots would actually focus on the background or their ears or other parts of the bodies.

So does it get better?

For my tests, I am using the FUJIFILM X-T5 and the XF18mmf1.4, which has Linear Motors. This lens is great at AF and should not be a limitation for the focus test.
I then made 2 tests - both with the old and the new firmware.

1st test - Walking from Left to Right

For this test, I am simply walking from left to right of the camera and observe the tracking as well as the final results of the pictures. What I can see is that the older version does have a lot more false positive than the new firmware. The tracking also tends to get more stuck on other objects and the newer version definitely improves the tracking itself. The hit rate is also improved - I get an overall significant improvement in the same conditions for the AF by upgrading to firmware 4.0 in this case.

Version 3.1

Overall, the hit rate with the new firmware got MUCH better. There is way less false positive now and when I bring to Capture One, I do see the AF improvements so it does look like the issues have been tackled. Now is it perfect? No but the improvement is definitely welcome.

Version 4.0

2nd test - Walking Towards and Away from the camera with back light

Version 3.1

For this test, I am walking away and towards the camera with some backlight to make things a little more challenging. And this is where I can see quite a big difference between the 2 firmwares. On v3.1, the algorithm get stuck to a piece of fabric on my mirror and while the focus is supposed to be following me, it just does not. The newer version fixes that and the difference is drastic. A very big improvement. It seems like FUJIFILM has listened and actually improved the AF capabilities of their camera.

Version 4.0