XF 70-300mm, quite often declines to AF, even in bright conditions

[Gion]

I experienced quite often the refuse of the XF 70-300mm to focus on AF on X-S10. This happens in various light conditions, the first time was in bright conditions. I am wondering this happens on other bodies too, or is the fault of the lens itself,  that needs a new firmware?

Edited June 26, 2021 by Gion

[BobJ]

I have not experienced this with my new 70-300. In fact the auto focus is very quick and positive indeed. I don't  know what the problem is but perhaps the lens is faulty.

[Gion]

It is the worst fault, 80-85% of the time is AF-ing, and 20-15% not, even in bright conditions (on X-S10).

[arachnida]

Hi, was this problem solved in a FW update? Today I tested out a second hand X-S10 with my own XF 70-300 (+TC 1.4). This lens works fine on my own X-T30, but was out of focus on the X-S10. Camera was set to M, it did focus most of the time on A but quite often, especially when moving from a nearby object to an object in the far distance and full zoom it didn’t manage to focus but did show a green rectangle. The focus was not a bit off, it almost seemed it stayed at the previous state. Sometimes, after switching back from “A” to “M”, it worked for a few shots but then it refused to focus again. On my own camera there is never a problem.

I must say that the tested camera’s FW was still on 1.1, wasn’t able to update the FW to the latest during the test.

So I would like to know if this was solved for the original poster of this topic in later updates? Fuji remains very vague about certain bugs and I didn’t see any notice in the later FW notes about the combination of this lens and body.

[arachnida]

14 hours ago, cpX said:

That sounds to me like the AF-On button is active.

We did a full reset of the camera and also the lens didn’t focus sometimes, so I think this can’t be the problem. It did focus a few times after going from “A” to “M” mode, put the longer we tried in “M” the more problematic it became.

[Nicole D]

I am also running into this problem. I am using the XT5 and increasingly having focusing problems with the 70-300 while all settings are checked, so this is not the problem. Has anyone found a solution to the problem?

[MARRIEDGUY9]

The firmware update helped me, seems to be better.  AF is not great at picking up moving birds in the sky, especially bright blue sky and a single bird, hit or miss, but otherwise OK.  Low light is a different story.

[SGinNorcal]

On 6/7/2022 at 12:45 AM, arachnida said:

We did a full reset of the camera and also the lens didn’t focus sometimes, so I think this can’t be the problem. It did focus a few times after going from “A” to “M” mode, put the longer we tried in “M” the more problematic it became.

You realize M is manual focus mode?  Also, the min focus distance has to be met or no focus.  I believe the min focus is longer with the 1.4 attached.

[mintumohan]

On 2/21/2024 at 9:06 PM, Nicole D said:

I am also running into this problem. I am using the XT5 and increasingly having focusing problems with the 70-300 while all settings are checked, so this is not the problem. Has anyone found a solution to the problem?

I am also on the same setup. I noticed on the photos once i look on my laptop screen. But I noted that issue in continuous autofocus mode and it looks ok on single focus. 

[Petone]

I'd had the 70-300 for about a year now.  

Unreliable focusing - especially at 300mm end. often focus behind subject is static and in center of frame.  Infuriating with birds for example!  You think you have a bang-on sequence of several shots and they often all turn out out out of focus.  I try shooting short bursts, then refocus and shot another burst - this has often saved me - but man this gets frustrating! :-(