Focus issues of Fuji GFX50

[mtakeda]

Lloyd Chambers has criticized a lot on this model's focus issues and quite frankly by looking at the images he put on I do not see what the problems are. I may not have trained eyes and I would appreciate it if anybody would help me to understand the points. Thank you in advance.

[siddhaarta]

I subscribe his medium format site, so I follow his tests with, let's say, critical interest. Obviously, some eyes are more forgiving than others, regarding technical aspects, as some eyes are more forgiving, regarding composition and art related aspects. 

His main working hypothesis is: why bother with MF if Nikon 810 with Otus lenses can make it better. you may follow that or not, but if you do, you have a high benchmark regarding image quality and lens performance which apparently the Fuji standard lens and zoom lens do not reach.

His observations are subtle but IMO clearly visible. The focus of these lenses (or at least his copies) seem to be really inconsistent, a bunch of problems with front- and backfocus, and focus-shift at different distances, and in the case of the zoom apparently a decentering problem. Not very inspiring for landscape shooters, at least for me. If you download for example the Pine Creek South Fork image from the zoom (far distance), it is impressive how sharp the lens is in the centre with very nice microcontrast and how bad it is on the right side. The normal lens has strong faint violet fringing wide open, etc. etc.

I would dare to conclude that Fuji made some serious compromises in order to keep the prices down, including lens design (interaction of hardware and baked-in software corrections in RAW) and QC.

Feel free to shoot me 

[kers]

I wonder what the use of the 50MP MF is if there will be a soon Nikon d8... 50MP.
According to lenscore.org the Otus 85mm can do 80MP wide open...
In my own tests i see that my Nikon lenses will do sometimes 130MP + in the center at the right aperture...

[fotagf8]

I am not particularly interested in the technical details--just the end product.  I've had the GFX for 2.5 weeks, and I am still figuring it out.  I haven't had a problem with the focus in terms of walking around with the camera on autofocus (as opposed to on a tripod).  I am inclined to shoot it in manual focus mode when on a tripod.  This afternoon I was taking a close look at the focusing tools built into the camera, and I was impressed with the various aids (including the screen that shows graphically the depth-of-field range, as well as the second smaller rectangle display that highlights a particular area.  Now I need to go out and practice with it.  As for softness at the edges, I have been satisfied with my prints, but I am going to go back and take a closer look.  I will say, that the autofocus is slow, but I didn't buy the camera to shoot sports.  It can take time for it to lock in, particularly if the light is low.

I do wish Fuji had not baked the lens profiles into the RAW files.  It would be nice to see exactly what is happening.

To some extent, there seems to be a "rain on people's parades" aspect to the recent discussion of medium format at a lower price point--I don't mean to suggest that it is you.  For the longest time, people hoped for a lower price entry point to MF.  Now that two manufacturers have given it to us, I've seen a spate of articles saying, "Not any better than FF 35mm."  Today (April 12, 2017), there was a review on PetaPexel by Ken Kaminesky of the GFX. You don't need to read the review.  Just take a look at the images he posted.  I imagine he can produce some very nice prints with those.

Whether it is the Hasselblad X1D or the Fuji GFX 50s, both cameras produce great images.  I can better say that in the case of the GFX since I have only seen X1D images that others have created.  No doubt that both Hasselblad and Fuji have their competitive juices running, which means that we can expect to see firmware improvements and second generation cameras will deliver even better images. 

My main issue with the camera so far is that it is not a tech camera.  Obviously I knew that when I bought it, but I also use an Arca Swiss RM3di, and I really notice the absence of movements in terms of framing shots.  Having said that, the RM3di isn't the easiest camera to travel with, particularly with the lenses and extension tubes.

Good luck

[chrismuc]

I am currently also a subscriber of Lloyd chambers blog and generally I appreciate his very critical view on cameras and lenses.

But - as a user of the GFX w/ 63 - I have to disagree with many of his critics because I just don't see them. Of course I only can speak for the GF 63f2.8 lens, because that's the only one I got (yet).

AF focus accuracy
If I select a small focus point and twenty times focus at open aperture to objects (w/ sufficient contrast) in various distances I 19 times perfectly catch sharpness at the focus area and 1 time I'm slightly off.
Of course focusing is not super quick because of contract detection but everyone knows that phase detection is technically impossible with this generation of Sony sensor, for that feature one has to wait for a camera update in 2018/2019 using the upcoming 100 MP BSI sensor.

Manual focusing
Of course it's focus-by-wire but IMO well implemented with very little clearance when focusing back and forth close to the perfect focus point.
It's true that somehow the image in the EVF or back screen does not 'pop' so much into the focus than other cameras (I will do a comparison w/ Sony A7RII) but I see no problem to focus correct manually, as I have to do using the Zeiss ZE 135f2, Leica R 180f3.4, Canon TSE 17, 24 a.s.o..

GF 63f2.8 performance
I would rate my Fuji 63 sample as one of the best lenses that I know and have, summing up all characteristics:

Sharpness
Center sharpness is perfect at any aperture (apart from diffraction closing more than f8 of course), corner sharpness is already impressively good at open aperture, very good at f4 and excellent at f5.6. My sample is also very evenly sharp at all four corners.

Focus shift
I did tests using a tripod, manually focused at open aperture at f2.8 to f11 at about 2 m and 3 m. Can't find any focus shift that would diminish image sharpness.
And: In autofocus, the lens focuses at the chosen working aperture (like Sony A7), so even if a certain amount of focus shift would be apparent, it would not cause any trouble.

Distortion
Fuji incorporated automatic correction for distortion, light fall off and chromatic aberration into the raw file (and the jpg, but I don't use). ACR carries out the corrections accordingly so one can't see them - normally .
Only if opened in Iridient X Transformer, switched off the auto-correction, exported as DNG and opened in ACR one can see the effects. Distortion is very little, maybe 1%, light fall-off at open aperture also, maybe half a f-stop, CA too. I see no problem in the auto-correction because I anyhow would apply it in ACR (apart from the fact that ACR adds a slight concentric wave pattern interpolation artifacts towards the image corners correcting the distortion, visible especially in darker even areas, but that's an Adobe fault, not Fuji's).

LCA
Very little greenish/ reddish halos back/ in front of focus point.

Bokeh
IMO absolutely great, one of the best I am aware of: soft transitions in the out-of-focus areas and absolutely round out-of-focus lights (at open aperture).

Otus comparison
Chambers every 20 lines of his blog writing repeats that the Otus (55) is better than the GF 63. The Zeiss Otus lens line is close to perfection, no question, but I don't see the point to compare again and again a manual focus 135 3K EUR lens with an auto focus medium format 1.5K EUR lens.
I anyhow would rate the resulting image quality of the GF 63 to be very close to the Otus (at comparable apertures).
I don't have an Otus but maybe I do a comparison to the (IMO also excellent) Sony/Zeiss FE 55f1.8 next weekend.

So far I'm perfectly happy with the camera and lens (just waiting for an one f-stop faster version ;-).

[mtakeda]

Thank you, gentlemen for positive input. I have seen many image examples including the one on Petapexel and been very impressed with high degree of resolution and sharpness. In the end unless there is fatal defects in products it is individual choice not by the other. And I have not seen such defect and as a matter of the fact the camera is quite opposite. Thank you again.

[hubell]

I am currently also a subscriber of Lloyd chambers blog and generally I appreciate his very critical view on cameras and lenses.
Manual focusing
Of course it's focus-by-wire but IMO well implemented with very little clearance when focusing back and forth close to the perfect focus point.
It's true that somehow the image in the EVF or back screen does not 'pop' so much into the focus than other cameras (I will do a comparison w/ Sony A7RII) but I see no problem to focus correct manually, as I have to do using the Zeiss ZE 135f2, Leica R 180f3.4, Canon TSE 17, 24 a.s.o..

We can quibble till the cows come home about many things in assessing the accuracy of Lloyd's evaluation of the GFX lenses. However, having used a GFX for 30 days, there is no question to me that he is right in concluding that the implementation of manual focus in magnified live view in the GFX EVF is unacceptably poor. I have a Sony A7RII and an X1D, and there is no comparison with how crisply the perfect focus point snaps into and out of place in the EVF with those two cameras. With the GFX, you move the focus ring back and forth struggling to see  where the perfect focus point snaps into place. This is readily apparent if you compare the GFX side by side with the A7RII or the X1D. It is mystifying to me, as the specs on paper of the GFX EVF are so superior.

[Michael Erlewine]

We can quibble till the cows come home about many things in assessing the accuracy of Lloyd's evaluation of the GFX lenses. However, having used a GFX for 30 days, there is no question to me that he is right in concluding that the implementation of manual focus in magnified live view in the GFX EVF is unacceptably poor. I have a Sony A7RII and an X1D, and there is no comparison with how crisply the perfect focus point snaps into and out of place in the EVF with those two cameras. With the GFX, you move the focus ring back and forth struggling to see  where the perfect focus point snaps into place. This is readily apparent if you compare the GFX side by side with the A7RII or the X1D. It is mystifying to me, as the specs on paper of the GFX EVF are so superior.

I agree. I waited about seven months for my X1D and then cancelled the order and bought the GFX because it looked to be superior to me. But when actually used, the GFX was (for me and my work) disappointing. Too much quality somehow shaved in lens development to keep the costs down. So, back it went. I now have a copy of the X1D and am finding my way how to use it properly. I listed my comments in the X1D impression thread for those interested. But it works well.

[Christopher]

No problem with manual focus at all. Certainly not any worse than my d800 which was the worst camera I have used live view on. (Not counting CCD backs...)

For my shooting style (stopped down to at least F5,6) there never was any real benefit from the Otus Glas. That was also the reason when I used my Nikon, after testing the Otus for a week I decided it was a waste of money. (Don't get be wrong they are amazing lenses, just not better for my style)

The Fuji Glas is great as is the X1D. Nothing amazing but very very solid.

Just one side note, I really don't understand how someone can find the X1D 90 any better than fujis 120. In my week of testing both it certainly wasn't.


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[Paul2660]

I don't read Lloyd, but from his comments that have been posted it's apparent to me he is not a fan of Fuji cameras, period.  If you don't feel that has some effect on his opinion, I would strongly disagree.

There have been a lot of comments on lack of quality of the Fuji Glass:

My comments are that the optics are excellent, and yes they are light weight but I am happy to have 1/4 the weight of a P1 Schneider LS lens if I can see the same optical quality, which I do with all three of the lenses I have.  I fully agree on Christopher's comments on the optics thus won't repeat anything.  They are overall excellent to my findings.  The 32-64 has a bit of rectinier distortion @ 32mm and on the far left side mine is a bit softer.  So I can't give that lens a 100% great overall review.  But so far I have found it to interfere with any photography.  The 120mm is amazing and so is the 63mm.  The fact that Fuji did not use a LM on the 63mm is a BIG disappointment to me as it's AF speed is much slower and it will hunt much more often.

There have been a lot of comments on the issue of baked in sharpening on the Fuji Raw:

If you use non supported raw converters on the Fuji Files, which would have no way of reading anything baked in, the files appear fine and sharpen up just they do in LR.  I personally don't believe it's possible to bake in a sharpening setting to any file but I will leave it at that.  Yes, Fuji bakes in the optical corrections to the files that has always been the case with all Fuji cameras, and yes LR will see these and apply them, there do not include sharpening.

There have been several comments on the fact that Fuji bakes in diffraction corrections to the raw:

If you use any Fuji camera and turn on "lens Optimization" yes, Fuji will bake in diffractions corrections to the jpg files.  THESE ARE NOT supported by raw converters like LR or ACR or even C1 (on the supported x-trans cameras).  This has been published many times as these raw converters developers did not want to take the time to figure the algorithm that Fuji used.  I have no reason to believe that for some reason, this now works on the RAW for the GFX.  I have contacted Fuji US and they have told me the "lens Optimization" only applies to jpg and IN CAMERA RAW conversions where the Fuji optimization data can be read.

There have been many comments on the lack of ability to use Magnified Live View to manually focus:

Again, it's possibly that users don't have a good understanding of Fuji cameras.  With Fuji you have two options for the EVF to display the file.  As it is with exposure taken into account.  And a more wide open max lighted view (display preview off).  This 2nd option will give a fully lit view for live view display but you can easily over expose the image since you may forget to read the exposure meter on the far left.  With the preview effect off, even in very low natural lighting I have no problems with manual focus in Live View.

There have been many comments on the lack of sharpness in magnified Live View:

Yes, if you zoom in all the way the details will be hard to see.  Please understand if you are zoomed in all the way, you have zoomed way past a 100% view, more like 150%.  This is similar to attempting to view an image on a D810 in live view with the magnification zoomed all the way in.  Net you really can't tell much.  You have 3 zooming options for the Magnified live View, and I tend to use the one in the middle.  If you are attempting this without peaking enabled, I believe you will have a lot more trouble determining good focus.   

Also, please understand that in preview mode, if you hit the zoom button one time, the camera's default zoom is WAYYY past a 100% view, and you can't determine accurate focus.  I no of no way currently to dial that one touch zoom down like you can with Nikon.  But you can pinch the screen like with an iPhone to shrink the maxed out view back down.  In my experience you need to zoom out close to 1/3 of the default view.

Can't compare to the X1D as Hasselblad is still shipping these in a very limited amount. 

I just have issues with the fact that it appears that some reviews don't understand anything about Fuji's design, and dive in, and then start making claims that the camera is defective, when it's clear they don't have a full understanding of Fuji's Focus by wire setup.  It's not perfect but it works.  If there is a fault for sure the way Fuji designed the neck strap lugs is a bit stupid?  They make the use of any other type of strap hard to do and the lug will flip around and get in the way of the memory card door.  I prefer to use the Peak Design straps.

Paul Caldwell

[kers]

....No problem with manual focus at all. Certainly not any worse than my d800 which was the worst camera I have used live view on. (Not counting CCD backs...) ....

So manual focus on the GFX50 with liveview is not worse than the worst camera that you have ever used?
that is reassuring...

The problem with the d800/d800e liveview was you could not see a 100% image; the d810 does not have this problem anymore.
What still can be better is the image quality in low light.

[chrismuc]

IMO that manual focus life view issue is totally exaggerated by some users (and reviewers). It's just that the sharpness doesn't pop in so much like at certain other mirrorless cameras, still MUCH easier to focus properly than on a DSRL with split screen. I guess other brands just do a stronger realtime sharpening of the life view image, so it make that image look sharper. Fuji easily could achieve this by a future firmware update. But that functional detail is for me not at all a dealbreaker to choose the camera or don't or choose the X1D instead. To get the camera in operation within about 2 seconds (instead of 4-5 seconds like the Sony A7RII or 10-15 like the Hasselblad X1D), to choose the focus point (and size) on the fly with the joy stick, to have a two axis tilt display, the availability of rather fast 50/85 mm equivalent lenses (63f2.8 and 110f2), to achieve 4x battery life and 8x w/ battery grip compared to the 1DX and of course to be able to adapt quite any lens w/ sufficient image circle to the camera, the reliability of a Fuji product, all that together made me choose the GFX, the slight imperfection of manual focus does not play any role to that decision.

[Michael Erlewine]

I would dare to conclude that Fuji made some serious compromises in order to keep the prices down, including lens design (interaction of hardware and baked-in software corrections in RAW) and QC.

After purchasing the GFX and working with it, I came to the same conclusion. The lenses IMO are not remarkable or if I remark it is like this. Of course, each one of us must have a threshold for lens quality that we look for. So, I can understand where some folks will say the GFX lenses are just what they want. All I am saying is that they are not just what I want. I wish they were, because the X1D system (which I now am testing) is quite a bit more expensive, etc.

As for the folks that comment on Lloyd Chambers forums and on his approach: I find Chambers very accurate and I should point out that he is like the last of the real lens reviewers who even bother to cover lenses. Please tell me who does as much or a better job and please include their links and I will check them out.

[Paul2660]

The best review is the one done by yourself.   You found it unacceptable. End of story.   I find it works very similar to other Fuji cameras and kept it.

It's possible to study some things to death.

I don't read Lloyd. I use a camera and if it works I keep it. I personally find it hard to follow a review where the user is so negative against the product.   

The micro focus on issues that things are being taken too amazes me especially when it's clear that many basic working features is the GFX have been misunderstood by certain reviewers. If LLoyd is unable to take a useable image with the GFX then shame on him.

To call the lenses cheap and or under performing is also a bit disappointing to see.

Paul Caldwell

[hcubell]

For anyone who doubts Lloyd's point about how poorly implemented the magnified live MF focusing is with the GFX, don't take his word for it. Pick up an X1D or a Sony A7rII and compare it side-by-side with a GFX. The difference in the ability to achieve perfect focus is shocking.
BTW, like most of the reviewers who drink the manufacturer's Kool Aid and don't critically evaluate what they purport to be "reviewing",  Lloyd calls it like he sees it. Lloyd may not like Fuji X series cameras, but he explains WHY he doesn't based upon the way he works. And Lloyd is no Hasselblad apologist either. He has carefully analyzed the AF errors in the X1D that are apt to occur in certain cases and he called it out loud and clear.
I don't know what it is with Fuji and the GFX. It feels to me like a cult where no criticism is allowed by the members and all members jump to defend the object of the cult if an outsider criticizes any aspect of it. Geez, it's a  camera! Calm down.

[Michael Erlewine]

I feel that this topic is getting gnarley. For me it is useful for those among us who have actually bought a camera like the GFX (or the X1D) to give our comments. I have no previous experience with or attachment to either Fuji or Hasselblad. Share experience and comments, but let's have respect for different points of view and uses.

[Paul2660]

For anyone who doubts Lloyd's point about how poorly implemented the magnified live MF focusing is with the GFX, don't take his word for it. Pick up an X1D or a Sony A7rII and compare it side-by-side with a GFX. The difference in the ability to achieve perfect focus is shocking.
BTW, like most of the reviewers who drink the manufacturer's Kool Aid and don't critically evaluate what they purport to be "reviewing",  Lloyd calls it like he sees it. Lloyd may not like Fuji X series cameras, but he explains WHY he doesn't based upon the way he works. And Lloyd is no Hasselblad apologist either. He has carefully analyzed the AF errors in the X1D that are apt to occur in certain cases and he called it out loud and clear.
I don't know what it is with Fuji and the GFX. It feels to me like a cult where no criticism is allowed by the members and all members jump to defend the object of the cult if an outsider criticizes any aspect of it. Geez, it's a  camera! Calm down.

No cult, just mis information.  As I have pointed out.  It's all dependent on how you have the camera setup.  I have access to the A7r, and rII, and own the D810 and 800.  I don't see any problems.  They all view the same and if you magnify the Sony IMO it's at times just as hard. I do take and have taken exception to the comments that the lens are cheap and not up to the standards of MF from some.  That's just not the case.  The optics are amazing.  The issue of baking in sharpening is IMO totally false, as I have stated, just use a non supported raw converter that doesn't even know that file is from a GFX, they look the same as a LR conversion.  This is easy enough to test for anyone the process has been well enough documented.

All I am trying to point out is people are attempting to take one seemingly mis informed, pre disposed review and make it the definitive answer to the camera and that is tragic.   

You and I disagree on the magnified live view use.  No problem.  Both opinions matter as we obviously view the needs or use differently.  Neither opinion is the definite just like Lloyd's is not either.  I can clearly state that if you don't have the preview options setup correctly and the camera is not giving you the max viewable image then yes magnified Live View on the GFX can be difficult, just like it is on any other Fuji designed camera.  From you use of the X1D I have no doubt that they are doing something like P1's Live View and automatically adjusting the exposure to allow for easier focus without need to make any menu changes which is also fine.

Paul Caldwell

[Brad P]

+1 for reliability of Lloyd Chambers' reviews.   Whenever I get serious about switching main camera platforms (as I am now), I research things to death and resubscribe to his website.   There are only a few really reliable and truly independent sources of info in the camera world, and a reason it costs a pretty penny to get access to Diglloyd. In my experience, time has proven out the quality of his initial equipment reviews. 

On paper, the GFX actually looks better at least to me than the X1D.  That doesn't appear to me to be the case generally reading/seeing people's early experiences.  Knowing lenses and peripherals are more important from a long term investment perspective than the camera back and seeing discussions like this, I may have to bite the bullet and get the X1D.  It appears to be on a reasonable path to the future -- mirrorless, likely at least competitive lens-wise with the best, the back is good but has room for improvement over the next 2-5 years (especially as better 100mp sensors roll out).  More expensive than it needs to be maybe, but I guess I have some faith that will keep Hasselblad at the leading edge. 

[Jim Kasson]

I'm a little late to this, but I can respond to a few of the points made.

I find that the magnified focusing experience with the GFX is a step down from the a7RII (which was a small step down from the a7R) when peaking is not used. When peaking is used in conjunction with mag view, I find the GFX works well. You may have to mess with the peaking lenels to find the one that works best with your chosen lens and magnification.

With respect to comparing the Fuji 63 to the Otus 55, I have done an on-axis quantitative testing on the GFX with the 63 and the Otus 85 (not 55, though I can do that if there's interest):

http://blog.kasson.com/the-last-word/fuji-632-8-focus-shift-and-loca/

http://blog.kasson.com/the-last-word/a7rii-gfx-on-axis-sharpness-w-otus-85/

They are quite different lenses. The Otus sharpest aperture is f/2.8. I think that's true of the Otus 55 as well. The Fuji sharpest aperture is f/5.6. The Fuji has more LoCA (the Otus has very little), but not a whole lot. The Otus at its sharpest aperture is sharper than the Fuji, but not by much. The Fuji focus shift is moderate at worst.

If you are comparing the Otus on the a7RII to the Fuji on the GFX, the Fuji is sharper on axis. It's not even close. On-axis sharpness is mostly a function of the sensor here, not the lens. For that reason, the Otus might be an even better lens on a higher-res sensor.

I did not do informal qualitative tests of the Otus 55 on the ar&II versus the Fuji 63 on the GFX, but here are tests that include both of those combinations:

http://blog.kasson.com/the-last-word/otus-55-on-d810-a7rii/

http://blog.kasson.com/the-last-word/zony-55-on-a7rii-fuji-63-on-gfx-50s/

If you poke around the blog, you can find tests with the 120 macro as well.

My take on the two Fuji lenses is that the 120 macro is a tour de force, and the 63 is merely very good.


Jim

[Brad P]

Great stuff, Jim.  Particularly happy to learn about the April 1 flooby dust issues    Also glad to read someone post about a reasonably good copy of the Fuji 63.

A long shot question -- are you contemplating comparing the X1D lenses anytime soon?   This kind of objective testing between the Fuji and X1D lenses I haven't seen yet and would be at least selfishly speaking unbelievably helpful.