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Dead pixel? on a week old Leica M


christianpsu

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Huh?

I'm talking about remaped lines not pixel!

My Canon 5D MarkII don't have any remapped lines. Maybe pixels but not whole lines! This is what i'm talking about. It's mystic why Leica have to remaps lines. on a CMOS chip.

 

Aren't lines made of pixels? I have no idea how the CMosis is read out, have you? By the fact that dead pixels create lines I suspect it may be a linescan sensor, which is not unknown. Dalsa is working on such sensors as well.

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Aren't lines made of pixels? I have no idea how the CMosis is read out, have you? By the fact that dead pixels create lines I suspect it may be a linescan sensor, which is not unknown. Dalsa is working on such sensors as well.

 

If it is deemed that an entire column of pixels must be mapped out, you effectively have 3976 dead pixels. Surely, this cannot be considered acceptable on a pro-camera, particularly one that sells for $7000.

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If it is deemed that an entire column of pixels must be mapped out, you effectively have 3976 dead pixels. Surely, this cannot be considered acceptable on a pro-camera, particularly one that sells for $7000.

Which is nonsense The line occurs because one pixel blocks the readout. I guess all digital medium format backs must be deemed unacceptable for professional use - their lines are even longer....

I wonder if anybody ever considered counting the manufacturing flaws in film emulsion?:rolleyes:

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So......... I finally got my M240 back. It was handed in on the 22nd of July and came back to Schmidt on 27th of August, so just a tad over 4 weeks I suppose which is relatively quick in my opinion. They told me 6-8 weeks so bearing that in mind, I was happy it came earlier than their quoted time frame.

 

So what were the service details:

 

- Repair pixel/line fault on image

- Adjust range finder

- Clean range finder

- Adjustments of all parts

 

Parts replaced:

- Board-set, calibrated.

 

To be honest, this is the first time I've come across the word "board-set" so wondering if any of you know what that is?

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Daniel, I had a call with Solms to that point. They told me that the problem is, that a dead pixel at thevend of a line can cause a problem in making the line ready to make a picture and in the read out. But it was a not so in deep answer. He thought, it is possible to skip this pixel, but they mapped out the whole line.

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So......... I finally got my M240 back. It was handed in on the 22nd of July and came back to Schmidt on 27th of August, so just a tad over 4 weeks I suppose which is relatively quick in my opinion. They told me 6-8 weeks so bearing that in mind, I was happy it came earlier than their quoted time frame.

 

So what were the service details:

 

- Repair pixel/line fault on image

- Adjust range finder

- Clean range finder

- Adjustments of all parts

 

Parts replaced:

- Board-set, calibrated.

 

To be honest, this is the first time I've come across the word "board-set" so wondering if any of you know what that is?

 

What did it cost?

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The only risk-reducing strategy I have come up with is target reduction, i.e. store the camera with the sensor vertical during flight. It is no scientific proof, but I have never had a dead pixel since I went digital in 1998. despite quite an amount of accumulated flying time -touch wood.

 

I would say that you have been statistically fortunate Jaap (as I have been). Cosmic radiation hits the earth from all corners of the universe and earth's gravity has an insignificant effect on it, so it is unlikely that camera orientation has any effect. Your best protection is earth's atmosphere so minimizing flying is the best prevention.

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I looked up some scientific literature on this, but it was way over my head. Maybe some physicist on the forum can comment?

 

I'm not a physicist, but my EE coursework required 2 years of college physics( which included 1 semester of nuclear/quantum physics - not my finest academic moment btw) and, later, having taken graduate level classes in cosmology, I'm fairly confident that orientation would have little effect. Even if the primary culprits were blasted at earth from the sun, keeping your camera upright - the earth's rotation would still expose the sensor face-on to the sun twice a day (unless the sensor was kept parallel with the equator while being kept upright). I'll just keep my fingers crossed. Besides, a hot pixel is easily corrected.

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Which is nonsense The line occurs because one pixel blocks the readout. I guess all digital medium format backs must be deemed unacceptable for professional use - their lines are even longer....

I wonder if anybody ever considered counting the manufacturing flaws in film emulsion?:rolleyes:

 

They certainly did. It was a most effective way to work out the manufacturing techniques of the companies involved. Different types of coating machines produced different types of defects.

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Just for reference, several years ago I got to work with a 4K CMOS-based large sensor movie camera that cost around $200,000. The manufacturer's spec allowed for three bad columns in a brand-new sensor (the camera I used came from the factory with 2 bad columns).

 

I can't get too worked up about a few bad columns. It's a very tiny drop in the image quality bucket.

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Well, there are dozens of threads on the subject here and in other camera forums and plenty of scientific -and less scientific ;)- papers on the Internet. A dead pixel is a pure matter of chance, as it is caused by cosmic radiation. As the sensor s read out in columns it can show up as a line. A sensor is more at risk during flights, especially transpolar ones, due to the higher intensity of the radiation. Sony is said to ship their cameras by land/sea for this reason.

Leica had a warning in the M8 and M9 manuals. I have not checked, but it is probably still there in the M manual.

 

 

.

 

Yes it's in the M manual too!

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  • 2 months later...

I found this thread after noticing for the first time after a couple of thousand pictures with my M, that there are 4 dead mapped columns. I took a picture of a building with repetitive elements, and they show the columns without mercy as purple lines. But never before, even with other kinds of repetitive patterns have I noticed anything. Kind of frustrating to notice the dead colums, but then, they seem to rarely cause any problems.

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  • 8 months later...

When was your M produced and what was the serial number?

I just took delivery of one which was dated 2014-01-14 serial 4824750 that had pixels issues as well.

 

 

So.... i only got the Leica M 240 a week ago and after i took it to a trip to Korea, I find this line going across the images. So I thought it was memory card. Swapped it for a new one. Same problem. Now I thought it was the actual LCD monitor that was the problem. Nope. When I was in LiveView, the line isn't there. Weird. So now it's getting shipped to Solms (teardrop) and have to wait for 6-8 weeks. The reason why I am posting this is because I couldn't find other Leica M owners who had this problem (yes, with other models but not for the new M). Please share your pain with me here if you have the same problem as me.

 

http://i1348.photobucket.com/albums/p729/christianpsu/1_zpsbfb2500d.jpg

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MM's both have dead pixels and spots. Both M240's have spots. All bot new. wont let Leica touch them. I just pretend it is film and spot them out. It is not like I wont be doing any PP anyway. Kinda sad a high priced cam goes out the door with these problems.

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Kinda sad a high priced cam goes out the door with these problems.

 

 

All digicams have dead or stuck pixels and some let you remap them or do it automatically. Leica does not, yet.

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