Quick test some XT2 owners can do?

[Adam Woodhouse]

On my XT1, when I stop down a lens (say F11) and look at the lens I can see it is still wide open (say F2.8).  When I engage focus, or take the pic, the aperture blades quickly stop down to the proper setting.  When I take the pic or release the focus, the aperture blades quickly return to wide open position.

 

On the XT2, what is happening is the aperture blades are returning from the stopped down setting to wide open very slowly.  I can watch the aperture blades over approx a 1 - 2 sec period slowly return to the lenses wide open state.

 

I noticed this because the LCD's on the XT2 will flicker as the aperture blades return to wide open.  Since I shoot most of my lenses wide open, I never really noticed this (plus on the XT1 the blades returned to wide open instant, so there was nothing to notice).  But on the XT2, I have tested 16/1.4, 35/1.4 and 16-55/2.8 and all very slowly return to a wide open aperture after I release the shutter (with a noticable LCD flicker).

 

Thanks

Edited October 14, 2016 by Adam Woodhouse

[kimcarsons]

Yes, all X-T2 (and X-Pro2) cameras do this. You'll also notice that in AF-C mode, all of the focusing is done with the aperture stopped down, which means performance is going to be very bad at any aperture other than wide open. I find it very suspicious that none of the 'professional' reviews mention this, which is a huge handicap compared to a DSLR (which only ever stops down the aperture when actually exposing the image). This was one of the many reasons I returned my X-Pro2... Was hoping it would be fixed in the X-T2, but apparently not---I'm likely to return it as well.

[Puma Cat]

Yes, all X-T2 (and X-Pro2) cameras do this. You'll also notice that in AF-C mode, all of the focusing is done with the aperture stopped down, which means performance is going to be very bad at any aperture other than wide open. I find it very suspicious that none of the 'professional' reviews mention this, which is a huge handicap compared to a DSLR (which only ever stops down the aperture when actually exposing the image). This was one of the many reasons I returned my X-Pro2... Was hoping it would be fixed in the X-T2, but apparently not---I'm likely to return it as well.

 

What do you mean by "performance"? 'Cause if it is autofocus performance, I don't agree and have the data to support it. 

[kimcarsons]

What do you mean by "performance"? 'Cause if it is autofocus performance, I don't agree and have the data to support it. 

 

Yes, autofocus performance. Anyone with an X-Pro2 or X-T2 can easily set the aperture to f/16 and do some focusing in AF-C mode to see it for themselves. Now try it wide open. Notice that the AF speed/performance is different. This is because PDAF requires a wide aperture. Now try the same thing on a DSLR. The aperture will be wide open during AF-C even though it's set to f/16 (it will only stop down when actually making exposures).

 

If you still don't agree, then by all means produce this data you have. I would be very interested to know how the X-T2/X-Pro2 can violate physics.

[Puma Cat]

Yes, autofocus performance. Anyone with an X-Pro2 or X-T2 can easily set the aperture to f/16 and do some focusing in AF-C mode to see it for themselves. Now try it wide open. Notice that the AF speed/performance is different. This is because PDAF requires a wide aperture. Now try the same thing on a DSLR. The aperture will be wide open during AF-C even though it's set to f/16 (it will only stop down when actually making exposures).

 

If you still don't agree, then by all means produce this data you have. I would be very interested to know how the X-T2/X-Pro2 can violate physics.

 

Kim, I'm not sure I am clearly understanding what the problem is; are you saying that AF performance is not up to snuff at smaller apertures? If so, check out my images from the Indy Car race I shot at Sonoma Raceway in the middle of September; most of these were f/11 to f/14 photographing racing cars at very high speeds. I found AF acquistion, lock and tracking to be exemplary. If there are supposedly "problems", I sure didn't see any...

 

http://www.fuji-x-forum.com/topic/3962-x-t2-rips-through-the-indy-car-race-at-sonoma-raceway/

Edited October 15, 2016 by Puma Cat

[kimcarsons]

Kim, I'm not sure I am clearly understanding what the problem is; are you saying that AF performance is not up to snuff at smaller apertures? If so, check out my images from the Indy Car race I shot at Sonoma Raceway in the middle of September; most of these were f/11 to f/14 photographing racing cars at very high speeds. I found AF acquistion, lock and tracking to be exemplary. If there are supposedly "problems", I sure didn't see any...

 

http://www.fuji-x-forum.com/topic/3962-x-t2-rips-through-the-indy-car-race-at-sonoma-raceway/

 

Perhaps you should try it in low light sometime. Obviously, the smaller the aperture, the less noticeable missed critical focus is going to be. Is CDAF at f/11, Good Enough? Maybe. But I paid a bundle for a camera with on-sensor PDAF and I'd like to use it. Nowhere in Fuji's marketing material does it mention that that feature only works in AF-C when the aperture is wide open. In AF-S, the focusing is done with the aperture open. I'm assuming that Fuji determined the aperture actuation was too slow to keep up with the burst rate and this why they keep the aperture closed in AF-C, but it really does defeat the purpose of having the PDAF system.

 

I don't have an X-T1 to compare with, but I do have the X70 which has a firmware a bit between the X-T10 and the X-Pro2. It does AF-C with the aperture open---not that the AF-C is usable on that camera.

 

After doing a bit of googling it looks like Sony users are having the same problem. Only apparently with Sony its firmware updates to the lenses that brings the new focusing-stopped-down functionality.

 

It would be nice to hear something from Fuji on why they think this and the slow/stepped aperture re-opening are features and not bugs---because they really look like bugs.

[jimlong]

I just saw this thread and tried the various things that were suggested.  What I found was that in single focus mode, the aperture did return to wide open very slowly, but, if you half-pressed the shutter, it would immediately go to wide open.  In continuous mode, it stopped down as soon as the shutter was half-pressed and returned to wide open when the shutter was released.  In very dim light, with continuous focusing, focus performance was very bad.  I could find cases where it would not focus at all (at f11) but would focus immediately if I switched over to single focus.

 

 

[kimcarsons]

I just saw this thread and tried the various things that were suggested.  What I found was that in single focus mode, the aperture did return to wide open very slowly, but, if you half-pressed the shutter, it would immediately go to wide open.  In continuous mode, it stopped down as soon as the shutter was half-pressed and returned to wide open when the shutter was released.  In very dim light, with continuous focusing, focus performance was very bad.  I could find cases where it would not focus at all (at f11) but would focus immediately if I switched over to single focus.

 

This concurs with my experience.

 

Something else, which may or may not be relevant (as it's not aperture related) is that sometimes the autoexposure takes a very long time to adjust (~10 seconds). Try turning the camera on with the lens cap on and then remove the cap. Sometimes the image will be blown out for 10 seconds. Sometimes it adjusts instantly. Also the auto ISO exposure when shooting video is (always) very slow to adjust to change in lighting---too slow to produce usable footage e.g. transitioning from indoors to outside.

[miguel]

I have just tried my XT2. The aperture stops down in AFC and AFS when focussing. An earlier post said it stayed open in AFS?

 

Are we saying that in low lighting AFS is more accurate focussing? and the camera focuses more accurate at wider apertures?

 

I have noticed in most lighting levels that when set to AFC the focus can hunt around the focus point, this could simply be me moving slightly with a hand held camera so I tried locking it down on a tripod.

 

In AFC at F2 on a 35mm lens in my kitchen, early evening light, when the shutter is held ½ depressed by a cable release, the camera focuses with the smallest AF single point set, the focus square goes green, then changes to white? After a sec or so it goes green again then changes to white. It will not lovk on green and stay there even though the focus point never changes, any idea why this happens?

 

Michael

[miguel]

I have just tried my XT2. The aperture stops down in AFC and AFS when focussing. An earlier post said it stayed open in AFS?

 

Are we saying that in low lighting AFS is more accurate focussing? and the camera focuses more accurate at wider apertures?

 

I have noticed in most lighting levels that when set to AFC the focus can hunt around the focus point, this could simply be me moving slightly with a hand held camera so I tried locking it down on a tripod.

 

In AFC at F2 on a 35mm lens in my kitchen, early evening light, when the shutter is held ½ depressed by a cable release, the camera focuses with the smallest AF single point set, the focus square goes green, then changes to white? After a sec or so it goes green again then changes to white. It will not lock on green and stay there even though the focus point never changes, any idea why this happens?

 

Michael

[kimcarsons]

I have just tried my XT2. The aperture stops down in AFC and AFS when focussing. An earlier post said it stayed open in AFS?

 

Are we saying that in low lighting AFS is more accurate focussing? and the camera focuses more accurate at wider apertures?

 

I have noticed in most lighting levels that when set to AFC the focus can hunt around the focus point, this could simply be me moving slightly with a hand held camera so I tried locking it down on a tripod.

 

In AFC at F2 on a 35mm lens in my kitchen, early evening light, when the shutter is held ½ depressed by a cable release, the camera focuses with the smallest AF single point set, the focus square goes green, then changes to white? After a sec or so it goes green again then changes to white. It will not lock on green and stay there even though the focus point never changes, any idea why this happens?

 

Michael

 

In AF-S, the aperture stops down after acquiring focus wide open. It all happens rather quickly. As soon as the focus square turns green, the aperture stops down (presumably to give depth of field preview? although, it does this even with "preview pic effect" off, which doesn't make much sense). But it's actually doing the focusing with the lens wide open. Try focusing on something with low contrast that takes longer to get a lock on. You can hear the aperture click on some of the lenses and also you can see the difference in depth of field in the preview.

 

In AF-C, the aperture is stopped down the entire time the camera is focusing, which is really pretty daft and makes one question the competence of the Fuji engineers. I mean, I'm in single shot drive mode here, so it's not like I even need an aperture mechanism that can open and close at 11 FPS.

 

Hopefully it's just a bug, but I'm not comfortable gambling $1600 on them deciding to fix this (and many other issues) in a future firmware update... I'll just re-buy the camera then (when it's hopefully cheaper and fully functional).

[miguel]

Hi Kim,

 

Tried out your suggestion, why do Fuji do it like this.

 

In AFC mode if you move the camera back and forwards on, for example, a newspaper, at f16 it hunts for focus, at F2 it manages to stay locked on the majority of the time. AFC appears to lock much quicker than AFC also.

 

As an ex Nikon shooter I always used the Back button , what I called the power focus of AF-ON.

 

I have set up the XT2 to work the same. AF-ON is assigned to the front Fn2 button because I find it easier to depress and the button sits well in portrait or landscape mode. I can fire the shutter with my first finger, focus with my second finger and move the ficus point with my thumb.

At the moment it seems to work well, need more time to test. I had considered the power battery pack but it weighs 330g, I can carry another lens instead.

 

On the plus side, its an excellent camera, the resolution is superb, comparing it with my ex Nikon D800. I only use Raw files which are first class, I do think Adobe could make them even better with updated algoriithms.

I shot some night portraits the other day at 6400 asa, with a little noise reduction in ACR they are quite amazing.

 

If you are the type of photographer ( which I am not ) who is happy to display his pics on a nice big monitor only, then set Aperture Priority, ISO Auto with max sensitivity of 6400asa, minimum shutter depending on subject, 1/125 with fujis shorter lenses is sufficient on non moving subjects and fire away concentrsting on composition and the ideal moment.

 

Sorry to rant on.

 

Michael

[Adam Woodhouse]

Thanks to those that have jumped into the conversation and shared their experiences on what the original post was asking.

 

I've found it interesting that what my camera does (the slow opening of the aperture after focus/picture is taken) is normal.  For what I do, I don't care about the changing aperture pre/post focusing either in AF-S or AF-C.  Most of the time I shoot wide open anyways and most of the time in AF-S.  What I do care about is the LCD flickering as the aperture blades slowly open from a smaller aperture that was used for a photo (say taking a family group shot @ F5.6 or a landscape @ F11).  I thought there was an electrical issue with the camera seeing the LCD flickering for no apparent reason (as I've not noticed it happening on my two XT1's).  

 

My hope is that it isn't necessary for the aperture blades to re-open slowly and a firmware update addresses that, which in turn addresses the screen flicker.

 

Fuji Canada service centre is aware of this as I've shared the info with them.

[kimcarsons]

Thanks to those that have jumped into the conversation and shared their experiences on what the original post was asking.

 

I've found it interesting that what my camera does (the slow opening of the aperture after focus/picture is taken) is normal.  For what I do, I don't care about the changing aperture pre/post focusing either in AF-S or AF-C.  Most of the time I shoot wide open anyways and most of the time in AF-S.  What I do care about is the LCD flickering as the aperture blades slowly open from a smaller aperture that was used for a photo (say taking a family group shot @ F5.6 or a landscape @ F11).  I thought there was an electrical issue with the camera seeing the LCD flickering for no apparent reason (as I've not noticed it happening on my two XT1's).  

 

My hope is that it isn't necessary for the aperture blades to re-open slowly and a firmware update addresses that, which in turn addresses the screen flicker.

 

Fuji Canada service centre is aware of this as I've shared the info with them.

 

Oh, I forgot to mention that we're not the first to notice this issue. People were reporting the flickering as soon as the X-Pro2 shipped. I can't find the thread but IIRC someone already contacted Fuji about it and they gave the typical response of "it's a feature not a bug." I think when people complained about the noisy aperture actuation, this stepped re-opening was Fuji's solution. The whole cluster of behaviors seems pretty sloppy. The most frustrating thing though, is that there are so many odd little problems with these cameras (and I'm not just talking Fuji here) that any pro photographer should notice first thing out of the box, but NONE of the reviewers ever mention, and if anyone harps on them too long on the forums, the threads mysteriously disappear. I think the only problem I've ever heard about from an official review source is Sony's overheating issue. It's a good thing Amazon has such a liberal return policy, but boy this kind of thing a waste of everyone's time and I'm getting tired of it.

 

I think there's a pretty good chance that Fuji will fix some of these bugs, eventually... But paying now and having to wait a year or whatever for the firmware update that turns it into a truly production ready camera doesn't seem like a great deal. 

[DerKnipser]

 

 

...

 

I have set up the XT2 to work the same. AF-ON is assigned to the front Fn2 button because I find it easier to depress and the button sits well in portrait or landscape mode. I can fire the shutter with my first finger, focus with my second finger and move the ficus point with my thumb.

....

 

Michael

That's what I tried. But how have you disabled the AF-ON function from the shutter button?

 

Gesendet von meinem SM-P600 mit Tapatalk

[miguel]

Hi,

 

In the Button Dial settings, change the Shutter AF setting to OFF

 

see page 224 on the downloadable manual

 

Michael

[DerKnipser]

Hi,

 

In the Button Dial settings, change the Shutter AF setting to OFF

 

see page 224 on the downloadable manual

 

Michael

thx have overseen this.

Regards

Sascha

[JasonK]

Hi,

 

Just reading through this thread. I know that other discussions about the AF system in the XT2 have mentioned that only a handful of the Fuji lenses can keep up with the XT2's focus system. From memory that list was something like this.

 

16-55 WR

50-140 WR

100-400 WR

35 f/2 WR

23 f/2 WR

 

The fast primes have all been reported as slow focusing. Have any of you experienced this issue with these newer lenses with the faster AF?

 

One other question I have is about the suggestion that one should test the AF system on very low light at f/11 or f/16. In what ciircumstamces would you need fast AF-C in lowlight and need a DOF of f/16?

 

Look forward to your replies. My XT2 is on the way and I want to be prepared.

[kimcarsons]

Hi,

 

Just reading through this thread. I know that other discussions about the AF system in the XT2 have mentioned that only a handful of the Fuji lenses can keep up with the XT2's focus system. From memory that list was something like this.

 

16-55 WR

50-140 WR

100-400 WR

35 f/2 WR

23 f/2 WR

 

The fast primes have all been reported as slow focusing. Have any of you experienced this issue with these newer lenses with the faster AF?

 

One other question I have is about the suggestion that one should test the AF system on very low light at f/11 or f/16. In what ciircumstamces would you need fast AF-C in lowlight and need a DOF of f/16?

 

Look forward to your replies. My XT2 is on the way and I want to be prepared.

 

The behavior is the same for all the lenses I've tried, which include the 35mm f/2 and the 55-200 (both very fast focusing). It doesn't not appear to be at all lens specific.

 

Try shooting someone walking/running/riding towards you with flash and you'll understand why you could want to use AF-C with smaller apertures. I imagine it comes up in sports/wildlife as well, although that's not my bailiwick. One doesn't always want razor thin depth of field.

 

N.B. f/16 is just an example to see the effect. f/8-f/11 is obviously more realistic. But anyone who's ever tried to shoot with a teleconverter on a DLSR knows well enough that phase detect AF breaks down very quickly as the f number increases and is useless beyond f/5.6.

Edited October 21, 2016 by kimcarsons

[Adam Woodhouse]

I have found my 35/1.4 to focus faster on the XT2 versus XT1.

 

This thread was started to ask if others have experienced when stopping down the aperture (i.e. F11) and take a picture, if the lens slowly or quickly returns to a wide open aperture after the picture is taken?  I have found on the XT2 that the aperture slowly returns to wide open (may take up to 2 seconds) which results in a flickering LCD while the blades slowly open up.