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X Vario AF Issues Follow Up


barjohn

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Earlier, there was a long post on the XV and AF issues. There was significant debate about whether the issue existed or was due to operator error. I conclusively illustrated that it was a camera issue. The question remains as to whether the issue only exists in a few cameras or is endemic to all XVs. I was encouraged to send my camera into Leica to have it repaired as there are several people that swear their camera never exhibits this problem/behavior and one person that said their camera did but they got a replacement and that fixed the problem. I did send the camera in to Leica NJ, as suggested, and it took a month to have it repaired. I was told they replaced the lens assembly and AF module. I received back the repaired XV with the strange firmware number. The camera is on its way back to Leica as the same AF problem still exists.

 

The camera will be focused on an object at distance X (tired with both spot and single point) and a green confirmation and beep will be given but on shooting the image the camera actually focuses at Y or Z where Y is around 1m and Z is at infinity. For example, you could be shooting a car door handle that is 5m distance but the camera will focus at 1m or infinity even though there is the garage door 7 meters from the camera blocking anything in the lens field of view further than 7m or it will focus at around 1m even though there are no objects at 1m from the camera. This happens randomly and the only consistent thing is that when it happens it either shoots at infinity resulting in nothing being in focus or it focuses at around 1m with nothing in focus. Usually this occurs in good bright daylight conditions with shutter speed above 250/sec and low ISO value. It can happen in low light too but not as frequently.

 

In both cases I have sent Leica both the DNG and JPG files that exhibit the problem along with the full EXIF data that shows where the camera focused (distance). My examples include where the camera focused correctly and with the next frame taken seconds apart miss focused.

 

My personal conclusion is that this may be a firmware bug but Leica is not acknowledging that a problem exists. They replace the lens assembly and AF module in the camera which would tend to exclude hardware. If it is a firmware bug, given Leica's slow history to provide firmware updates and fixes it could be a long time before this problem gets fixed. Given its random nature, I think it is just that they haven't noticed it and when they got an out of focus shot assumed user error without investigating further.

 

Below is an excerpt from my email to Leica illustrating the problem. Feel free to look at the images and down load them for your own investigation.

 

I am attaching several images that demonstrate the problem. They were all taken from the same position on a bright and sunny day within minutes of each other. One shows the correct focus and the other does not. The focus point for all images was the rear car door handle. A green confirmation box showed before the shutter release was pressed completely each time. I have attached the EXIF data for the selected files. I also have provided links below to the selected images.

 

Shot at 46mm

 

#198 Correct Focus: 1/250, f6.3, ISO 100, 1point focus, focus distance from EXIF = 41291 = 5.90m

 

#199 Incorrect Focus: 1/250, f6.3, ISO 100, spot AF, focus distance from EXIF = 65535 = Infinity

 

#200 Incorrect Focus: 1/250, f6.3, ISO 100, spot AF, focus distance from EXIF =1115 = 1.15m

 

#201 Incorrect Focus: 1/250, f6.3, ISO 100, spot AF, focus distance from EXIF =1030 = 1.03m

 

Shot at 23.2mm

 

#191 Correct Focus: 1/400, f5, ISO 100, 1point focus, focus distance from EXIF = 45815 = 6.55m

 

#192 Incorrect Focus: 1/400, f5, ISO 100, 1point focus, focus distance from EXIF = 540 = 0.55m

 

Link to DNG and JPG files for above: https://www.dropbox.com/sh/ylhjr1hc02o3r76/eVlP7Bog06

 

Here is the original examples and information:

 

The following link is to a DropBox folder containing several samples of out of focus shots. Files 1671 & 1672 probably illustrate the problem as well as any. The focus target in those two images was the chairs in the doorway. In each case the focus indicator turned green and the camera beeped before the shutter was pressed. I have included screen shots of the EXIF data. In particular see location HEX 040a, the first value is the distance the lens was focused. One must do a conversion to understand the value. If your technician is unfamiliar with the conversion algorithm please let me know and I can supply it for him. In short, one divides the value by 1,000 if the value is 30,000 or less and one gets the distance in meters. If greater than 3,000 you divide by 7,000 to get the distance in meters and infinity equals 65,535.

 

Below is the EXIF information showing for 1671 the focus distance was set to 1.15M and for 1672 the focus distance was set to 5.66M.

 

I have many other images but have provided a few samples only. I included the JPGs and DNG files for each.

 

Folder Link with Sample Images and screen shots of relevant EXIF data: https://www.dropbox.com/sh/pwgm68q1p1dqiip/mWoX1A_Mxl

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hallo john,

 

bei den autobildern könnte ich mir vorstellen, dass die kontrastfokussierung, je nach angemessener fläche (spotfokus vs. 1-feld fokus) nur das rot ohne jeglichen kontrast wahrnimmt und richtiger AF deshalb nicht möglich ist. warum aber das messfeld dann grün anzeigt ist unerklärlich.

bei dem scharfen foto wurde möglicherweise die schattenpartie, unterhalb der griffmulde, mit angemessen und der AF sitzt richtig.

bei den anderen beispielen ist die vermutung oder theorie wiederum nicht plausibel.

obwohl ich nun auch schon einige fotos geschossen habe, kann ich von derart abweichenden AF-messungen nicht berichten.

 

FAZIT: Deine kamera muß zurück nach solms/germany. ich wünsche Dir dass das problem gelöst und dauerhaft behoben werden kann.

 

kind regards klaus-michael

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Since I don't read German, I google translated kmhb's post and amposting it here for others:

hi john,

 

at the auto images I could imagine that the contrast focus, depending on the appropriate area (spot focus vs. 1-focus frame) only the red without any contrast perceived and real AF is therefore not possible. but why the measurement box will turn green indicating is inexplicable.

at the sharp photo may have been the shadow partie, below the handle trough, with appropriate and the AF is properly seated.

in the other examples or the presumption theory is again not plausible.

even though I already had shot some photos now, I can not tell from such different AF measurements.

 

CONCLUSIONS: Your camera must go back to solo / germany. I wish you that can be solved the problem and fixed permanently.

 

WDA, I'm not sure who your post was directed toward as I don't recall listing any reports or statistics.

 

kmhb, provides a possibility if that was the only example but as can be seen in the other examples, the conditions were much different and there was high contrast object to focus on. I have many other examples including portraits where I was across the table from the subject. I tried to post the examples that made it easy to see what was happening.

 

My big concern is that it is a firmware bug and intermittent. Leica is so slow at fixing firmware issues and releasing firmware patches that I would not be satisfied with waiting. The heart of modern cameras is computers and software. These two things are very different to master than mechanical lens construction and I think Leica is still in its early development stage in regards to both. One should anticipate that users will find bugs that the developers missed and be ready to fix them and deliver new patches quickly. So far, only a few companies have shown that kind of responsiveness. The alternative is to have no major show stoppers on release. That requires even more challenging engineering. I'll follow up as I hear from Leica.

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Hi Barjohn,

Thank you for publishing the result of your checks of your repaired X Vario -- albeit the results are not what you and any others have hoped for. I still believe that my X Vario suffers, at least, from similar problems. At the moment, other things pushed my X Vario issues to the background, though... And since I use spot AF, I also seem to have fewer issues -- but that's just an impression.

 

The reason why I post here is that I still believe that the "truth" is somewhere hidden in the Exif data. And when going on a first inspection of your new sample photos, I hit on a curious phenomenon: A difference in distance data between DNG and JPG files:

 

L1020191.DNG: 45815 (as you post; Panasonic Leica 5 0x040a, first double byte)

L1020191.JPG: 540 (Panasonic Leica 5 0x040a, first double byte)

L1020192.DNG: 540 (Panasonic Leica 5 0x040a, first double byte)

L1020192.JPG: 540 (Panasonic Leica 5 0x040a, first double byte)

 

So, a "conspiracy theory" might be as follows: When calculating the JPG data, the X Vario processor makes an error, and this error value is used in the next shot (somehow buffered...). Sounds weird, I know... But who knows, whats going on in the processor...

 

By the way, some time ago, I found a value of 65536 in the distance double byte, although focus was too close (usually, the focus was too close and the Exif data reflected this). Seems to be a "new" phenomenon -- or did you find that already?

 

So some food for thought & best regards, Gerd

Edited by waloszek
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Maybe I am just a lucky one, but i do not have any AF Problems with my X Vario.

When I have an out of fokus pic the Problem was definitly behind the Camera. ;)

 

The pics of the red car. It is an CDAF - contrast based. Where is the contrast on the door? All of my Fuji and Sony cameras fail there.

 

Other with the second Part of pics L1021671. I really do not understand what happened.:confused:

Same at 1567. Maybe the focus is on tree on the right and it was a bit of wind, the white flag tells me this.

I do not understand the Exif and where I find something about which kind of Af, distance and which subject the camera wanted to be sharp.

 

Sorry i know about my bad english, but hey, i am an old german.....:)

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I could understand why the car shots are mostly out of focus. Every AF system I've had so far needs a vertical edge in the position where it is to focus on. I can not understand why the camera gives every sign of having acquired focus when it has not.

 

I do not understand the interpretation of the exif data; why do they contain the text "Leica Panasonic 5" when the X Vario does not involve any Panasonic? Are there any templates being used which are meant to be used with another camera?

 

The shot with the chairs ought to be sharp, unless the camera has been moved between taking the distance and releasing the shutter. I can not see the cause for the problem.

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>> I do not understand the interpretation of the exif data; why do they contain the text "Leica Panasonic 5" when the X Vario does not involve any Panasonic? Are there any templates being used which are meant to be used with another camera?

 

I think this is an ExifTool issue. When I used older versions of ExifTool (for example, version 9.3.1), it was just "Maker Unknown" and "Unknown". Since I use version 9.39, its "Leica" for the maker and "Panasonic Leica 5" for the tags. Has probably nothing to do with Leica itself...

 

Best regards, Gerd

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Though I only had use of an X Vario for a few hours, they were a solid few hours of nearly continual shooting. "My' sample of the camera did not have those problems. It would probably be an easier fix for John's camera, and others reporting the same issue if the problems were universal. I wonder if John's quicker solution would be a replacement camera.

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When you try to understand such issues, you build a lot of (mostly wrong) "theories" -- at least, I do so... One of my "theories" is that the camera's processor might be "overwhelmed" by the mass of data. I found that when I took longer breaks between shots then there were no AF errors. I looked at the times barjohn took his photos. In the first set from last year, I cannot see any indication of this (the breaks in between are too long).

 

The new set is a little bit different, though. For the second photo he switched from 1-Point AF to Spot AF and took it after 10 seconds - result: the shot was taken at infinity. He took two more shots, each after 5 seconds - results: focus too close.

 

I would therefore like to ask barjohn whether he can redo his test: (1) with taking photos as fast as possible, (2) with taking a break of, say, 15 seconds between each shot.

 

Should the second set exhibit no AF failures, this might be a track to pursue...

 

Best regards, Gerd

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Since I don't read German,

 

hi john, I try it again with google translator.

 

in car photos, the contrast autofocus with "one-field" or "spot" measurement almost no chance. but why the AF green indicates I do not understand.

 

with the "multi-field" measurement of AF would have worked, because the black shadow under (on) the car door handle is enough contrast to the red of the body.

 

I can absolutely further exampels your not explain. to the calculations that lead to the EXIF-data, I can not say anything.

 

Gerd Walsozek is this an appropriate professional. See his current post: different measurement results JPEG vs. DNG.

 

I hope Leica read with you an Gerd not only with, but check and test the computational operations of the components involved in the autofocus.

 

Kind regards

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I hate to admit that I missed the fact that the AF distance computed by teh camera was different between the JPGs and DNG files of the same image. I did not post all of the images I took, but many were in focus, not just the one I posted. It is more of an issue of unpredictability as to when it will be and when it won't and why the camera says it is when it isn't. If the camera said it could not find AF and failed to turn green and beep, that would be understandable. That is not what happens.

 

I can't conduct any further tests with the camera as it is back in Leica's hands in NJ and I have told them I do not want it back. I want either a replacement that does not have this problem or my money back. I am awaiting Leica's decision.

 

Since we don't have access to their source code or the tools to debug such a problem there is no way for us to figure out what is actually causing the problem. Only Leica engineers have the information to diagnose the issue. As it is this camera is not going to be able to be relied upon to "capture the moment."

 

On the Leica-Panasonic being in the EXIF data, Gerd's assumption is one possibility; however, another possibility is that Panasonic is somehow involved in the manufacture. They may also be the partner in the upcoming Leica "T". Even though the X series says "Made in Germany," no one has seen the manufacturing facility that I know of on this forum and no pictures or video of the X series cameras being assembled (like they do for the M) appear anywhere. So just where is this mysterious German manufacturing plant located and why no pictures or video of assembly and testing? If it isn't a mystery for M cameras why should it be a mystery for X cameras? Food for thought. :)

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barjohn wrote:

>> It is more of an issue of unpredictability as to when it will be and when it won't and why the camera says it is when it isn't.

I agree. Usually, there are only a few photos out of focus, but you never know when and why. Therefore, I often take two or three photos (and stumble into an issue if I forgot to do that...).

 

> Since we don't have access to their source code or the tools to debug such a problem there is no way for us to figure out what is actually causing the problem. Only Leica engineers have the information to diagnose the issue.

I agree again. I like to play detective, but there are limits to what one outside of Leica can do...

 

Since barjohn can't do further tests at the moment, I just did a test with different focus modes on a framework wall about 2m away from me. I have to evaluate the zillions of photos that I shot, but can already give away a few results:

 

  • Spot focus: I could (just) point it on the black wood of the framework (more or less not structure). If I did so, I had it all: A mixture of red "confirmations" (but the results were not that bad), green confirmations with shots either being in focus, or a lot being out of focus (much worse than the red "confirmations"). I could see the wrong focus even in the viewfinder. I could already find this out by half-pressing the shutter release button without taking a photo, but I took photos to get the Exif data.
     
  • 1-Point AF: The AF field was larger that the framework was wide. I got always "green" focus confirmation, and I didn't realize any out-of-focus shots during shooting (I have to check that with the photos).
     
  • 11-Point-AF: There were a few misses, but always green confirmation. I have to check how many were wrong.

 

So, I will have to check my photos. Perhaps I can find the Exif tag, in which Leica stores whether focus had been confirmed or not.

 

All in all, there seems to be a firmware bug with respect to focus confirmation (perhaps coupled with a focusing bug...).

 

Anyway, I will stop posting on this matter now, and only "re-appear" if there is something worthwhile to report or someone asks me a question...

 

Best regards, Gerd

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I got my X Vario second hand. Up to now I did not have auto focus problems. I received following advise from the seller:

 

"quote"

 

As per focus mode, even though the manual suggests that "spot" is more precise than "1 point", in common usage it is just the opposite, as "spot" requires a lot of "vertical luminance contrast" to lock and is prone to return "false positives" (i.e., you get the green square but the photo is out of focus). I hope if Leica is working to fix the "spot" focus through a firmware update, as contrast based focusing is 90% software driven.

 

"unquote"

 

Best

 

Roger

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When I reconsider barjohn's AF issues and my test today (details: Leica X Vario: Functional Issues - Autofocus), it's primarily spot AF that confirms focus and then is "way off". Perhaps many users do not experience AF problems because they do not use spot AF... I may be wrong with this observation, but there is definitely a bug in the spot AF implementation ("green" focus confirmation together with resulting off-focus...).

Best regards, Gerd

P. S. Sorry, I had promised to keep silent for a while..

Edited by waloszek
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John, I totally agree with you! It should work!! Today I did try all AF options - no problems. But if you have a "complex" pic situation, e.g. several persons (party, street,etc) and you want to focus for example just one face, it is IMHO easier to use the manual focus in general instead of picking the "perfect" AF option (spot or whatever). But of course, like I mentioned above, the AF technology should work......

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