M9P sensor fixed by MAXMAX - big problem!

luuca

luuca

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hi, here you are my experience
I love my M9P and I trusted mr. Dan and I sent to him two mp9 (one mine, one of a friend of mine) that had the famous sensor issue.
payed 3000 dollars (plus shipping, plus taxes)
and today they returned to me.
both of them are unusable, showing a big difference between right and left part of the sensor sensibility.

the result is an image cut in half by a vertical stripe.





I told him about that and he said it is normal, because sensors bigger than apsc are stiched together and then normalized with the camera firmware by the factory.
He said I must complain with leica that made the camera.
Assuming he is right, the problem is that the issue wasn't present before his intervention and no one told me about that.
He suggested me to send it back to solms to ask to fix the problem by leica....

Now I wonder: how did he thought I would use my cameras? as a brick? 3000 dollars to have the more expensive paperweight of the world?

I only created this discussion to warn you about this unsaid (at least to me) issue.

I hope it could help someone to save money.

He knew about the possibility of this issue, he should warn me...
 
luuca said:
hi, here you are my experience
I love my M9P and I trusted mr. Dan and I sent to him two mp9 (one mine, one of a friend of mine) that had the famous sensor issue.
payed 3000 dollars (plus shipping, plus taxes)
and today they returned to me.
both of them are unusable....He knew about the possibility of this issue, he should warn me...
Click to expand...

I would contact Leica, be 100% honest with what you did and whose service you’ve used, the supposed fix and see what they reply. I have a feeling it isn’t going to be that you should send the camera to them, but at least you can send Leica’s reply to the people who screwed up the cameras. Did you pay via a method you can complain about?
 
payed with credit card.
I will sure contact leica.
maybe I will copy and paste the answer I received from maxmax
 
maybe leica used the glass that maxmax changed to correct this difference?
maybe the glass was somehow graduated?
 
I would keep all correspondences documented and then call your credit card company. Report "fraud" and ask them to reverse the charges.
 
I talked with Dan, my contact for MaxMax: he says the two things are not correlated.
but maybe the corrosion created this issue.
the m9p of my friend shows much less evidence of the stitching issue, probably because sensor corrosion just happened, while for my camera it's been months that it has the problem.
Now I wrote to Leica customer service to ask them if the theory of Dan is correct or at least possible.

for people interested in this, here is the explanation about sensor stitching:

BEWARE, WALL OF TEXT:

First off, all 35mm FF sensors are stitched. No way around it. The stepper reticles FOV used in fabs are not large enough to image a FF sensor in one shot. APS sensors can be made in one shot but they hit the limits on reticle aperture; in fact most APS sensors designs are reticle limited. Cost is a MAJOR reason why the digital camera industry way back in the day focused on APS sensors since they could build them on one reticle field.

Most fabs have reticle limits of ~30x30mm. I think TSMCs stepper reticles are ~26x~28. To step a 35mm sensor you need minimum of 2 shots; the 24mm active area fits on the 28-30mm field height, and you do 2 shots, L/R halves, so there is a stitch line down the middle. Medium format sensors are minimum of 4 shots.

Fabs HATE stitching since it screws up the ‘flow’ of steps/wafer/machine etc. The stitched wafers are in the stepper longer than the other wafers in the line since they have to shot multiple shots, and the wafers behind them only need one shot etc. Most fabs will stack up the stitched work and run it al lat the same time, like maybe once per month.

The stitch line has to be processed out or it will be obvious. It is impossible not to have some type of visible disturbance at the stitch boundary. If anyone ever tells you that they don’t have stitch boundary processing they are BS’ing. The reason is, if you think about it, the stepper lens is not perfect, and at the boundary, you are imaging the reticle with the left side of the lens on one shot and the right side on the other. That fact convolved with the accuracy of positioning the reticle at the boundary creates a very small anomaly that ends up disturbing how the pixel collects and processes the photon signal. These anomalies get more difficult to deal with as pixels shrink. The 4um pixels (45mp cameras) are much harder to make than a 6-9um (12-24mp). IMHO you will never see a ~150Mp 35mm camera for this reason. Yields on this device would cause the camera to price at $10-20K and nobody could afford it. Could it be built, yes, but the stitching artifacts would be larger and more difficult to deal with, probably causing lower ISO range too (super high digital gains in the ISP would make stitch management artifacts very difficult. Besides, there is a limit to ‘practical’ MP in DSLRs. At some point users won't pay, and the file sizes get stupid. They are better off investing in auto-focus, frame rate, or some other useful photographic aspects, not just pixel count. IMHO 35mm DSLRs will stop the MP wars at the 60-90mp tier. 60mp is a 3.8um pixel; 96mp is a 3um pixel (8x x 12k). ISO and dynamic range on a 3um pixel gets tough too for Pro performance.

From a stitch management perspective every camera has to be uniquely calibrated to remove the stitch boundary anomalies. Both the dark offset and responsivity has to be processed to match both halves at the boundary. Offsets are different since the column amplifiers are also on both sides of the stitch and this can affect how the transistors are made, etc. These are very small differences, 1-2DN, at most but make huge problems at high ISO when the digital gains are high. (A “DN” (digital number) is the RAW digital number coming out the A/D converter in every column; for a 14 bit ADC, the range of DN’s is 0-16383). Responsivity is a linear gain adjustment to match the halves. Typically they would uniformly light up the sensor to ~75% full range then measure the DN values after dark subtract. Then compute a correction gain. This gain may also be done at various ISO ranges to accommodate the sensors non-linearity across the full range. These offset and gain adjustments can also be done differently from the top compared to the bottom of the sensor, due to gradients affecting offset/gain across that distance (second order affects from the stepper, for example stepper lens distortions between the left/right halves)

When making a sensor the wafer is stationary and the stepper moves to each sensor location and images that mask’s information. The stepper images all the sensors, then that mask is changed out and the process repeats after the wafer returns from the other machine steps (for example the wafer are imaged then go to an ion implanter, then come back to the stepper for the next step, which could be metal dep). There are about 20-30 different masks needed to make a sensor. In the case of stitching, it takes twice as long since the sensors are imaged in 2 halves (for 35mm) with the same number 20-30 mask stack.

The stitch line is always visible if you don’t process it out; could be very subtle, but it’s there. For very large pixels it might not be visible, but that’s probably sensors with >10-20um pixels.

With your sensor corrosion, that certainly would have helped hide the stitch by blurring the image. So, like I mentioned before, I only changed the defective glass. The stitch line will be more obvious at things like small apertures and when the lens is at certain angles of light and depending on your post processing such as sharpening.

If the stitching line is really a problem, tell the Leica repair center that over time, your stitching line has become more obvious and ask them to adjust the camera firmware to process it out.
Click to expand...
 
hey, I don't want to throw a ****storm to maxmax without proof.

I just want to understand before I decide what to do.
 
luuca said:
hey, I don't want to throw a ****storm to maxmax without proof.

I just want to understand before I decide what to do.
Click to expand...

Three thousand dollars for a repair that didn’t work? It’s obvious to me what to do: Refuse to pay that money, not accept ridiculous techie talk as an explanation, and send both cameras to Leica to have them repaired correctly.

And don’t rely upon that company for service in the future. Simple.
G
 
Wow - That wall of text doesn't go down very well. My take from it is that it's "YOUR PROBLEM NOW". Anybody know if it's BS?

I had my own awful experience with MaxMax several years ago. I would never recommend them to anyone who values good customer service when problems arise. People make mistakes, sure, but it's the handling of those problems that counts. I'm sure they're "fine" when nothing goes wrong, but if it does watch out. They apparently do not like to accept responsibility for problems they create.

I sent a D700 to them for removal of the anti-aliasing filter, and when I got the camera back there were streaks in the image that weren't there before. I sent the camera back to them, and they supposedly replaced the piece of glass they had installed the first time. The guy I spoke with was irritated when I suggested they test things before sending them back out. Then, when I got it back, the sensor issue was fixed but the battery grip no longer worked with the body. This was not acceptable for me because I used that camera professionally and needed the extra battery capacity for long jobs.

I talked to the guy on the phone again, and he was defensive and unhelpful, wanted to argue about my use of the term "battery grip", and angrily told me to send the camera back again. I sure didn't feel like sending my camera back to someone with such a poor attitude, so I fixed the problem myself. I removed the back from the camera and found that they had failed to reconnect the ribbon that goes to the grip contacts on the bottom plate. It was obvious, and an easy fix. I never bothered to call MaxMax and follow up with them, choosing to spare myself the abuse.
 
not so simple.
at the beginning he told to me that he would only fix the corrosion and no others issues related to the sensor itself. I told him that the cameras were perfect.
now I want to know if this issue is related to his job or to the sensor corrosion.
Maybe tomorrow leica will answer to this question.
 
Godfrey said:
Three thousand dollars for a repair that didn’t work? It’s obvious to me what to do: Refuse to pay that money, not accept ridiculous techie talk as an explanation, and send both cameras to Leica to have them repaired correctly.

And don’t rely upon that company for service in the future. Simple.
G
Click to expand...

I agree with this. If you haven't received the service that you paid for or the product is not fit for purpose or below the promised standards then you have the right to refuse payment.

Three thousand dollars is a lot of money for something that is not usuable.
 
GMOG said:
Wow - That wall of text doesn't go down very well. My take from it is that it's "YOUR PROBLEM NOW". Anybody know if it's BS?

I had my own awful experience with MaxMax several years ago. I would never recommend them to anyone who values good customer service when problems arise. People make mistakes, sure, but it's the handling of those problems that counts. I'm sure they're "fine" when nothing goes wrong, but if it does watch out. They apparently do not like to accept responsibility for problems they create.

I sent a D700 to them for removal of the anti-aliasing filter, and when I got the camera back there were streaks in the image that weren't there before. I sent the camera back to them, and they supposedly replaced the piece of glass they had installed the first time. The guy I spoke with was irritated when I suggested they test things before sending them back out. Then, when I got it back, the sensor issue was fixed but the battery grip no longer worked with the body. This was not acceptable for me because I used that camera professionally and needed the extra battery capacity for long jobs.

I talked to the guy on the phone again, and he was defensive and unhelpful, wanted to argue about my use of the term "battery grip", and angrily told me to send the camera back again. I sure didn't feel like sending my camera back to someone with such a poor attitude, so I fixed the problem myself. I removed the back from the camera and found they that had failed to reconnect the ribbon that goes to the grip contacts on the bottom plate. It was obvious, and an easy fix. I never bothered to call MaxMax and follow up with them, choosing to spare myself the abuse.
Click to expand...

thanks for the feedback...
I also think that there's some responsability.
tomorrow I will contact my card company to understand what I can do
 
Do you see this problem in the files after transferring them to your computer? Asking because the images you provided show pictures displayed on the back of the camera.
 
yeah, the issue is also in lightroom.
both in dng and jpeg, at low or high iso, with different sd cards, different battery
 
I was going to post some info relating to the thread but, My god does /imgbox.com blow or what? I even have to look at the porn ads under the posted image. WTH
 
It seems that these sensors are made from two halves and merged together by firmware inside the camera. Normally, you can't see the line between the two, but there are reports of similar problems with other Leicas every once in a while. Here's a discussion of a similar problem with a M10M: https://www.l-camera-forum.com/topic/316688-m10m-gate-coming/?do=findComment&comment=4129376

I'm guessing here, but there's probably a calibration procedure at the factory that equalizes the data coming out of the two halves to that they look the same. This calibration info would be stored semi-permanently inside the camera body (i.e., not on the sensor itself and not on a SD card).

Is it possible that the corrosion repair shop accidentally put a sensor from one body into a different camera? That would mean the calibration data in the body wouldn't match the electrical output from its sensor.

If that's what's happened, it's the repair shop's fault, but could probably be fixed by a trip to the Leica factory.
 
MAXMAX uses a different glass, closer to that used in the M8. I suspect the transmission is different. The M9 sensor is "stitched", and uses what we used to call "Non-Uniformity-Correction", or NUC. This means the two halves of the sensor are calibrated, and corrected either through analog gain before digitization or are corrected numerically after being digitized.

I would suggest shooting grey cards of different values, ranging from black to white. Determine how the two sides differ. Post the results. It might be possible to perform the NUC on the images to bring the two halves of the image back into calibration. It depends on the nature of the drift between the two halves of the image.
 
The sensor needs to be remapped, why this became obvious after the coverglass was replaced is unclear. The sensor remap would be a normal part of the service from the manufacturer, but MaxMax obviously cannot do this. They said they would fix the corrosion, which is presumably fixed.

I have seen several repairs from MaxMax and Kolarivision where the cameras came back good as new e.g. in this thread: https://www.dpreview.com/forums/thread/4519454

I suggest continuing to press MaxMax and talk to Leica about sensor remapping.

Marty
 
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