Jump to content

Vertical line from dead pixel?


efix

Recommended Posts

Advertisement (gone after registration)

Dear forum users,

 

I recently discovered that in my M8's high-ISO shots, a vertical line is visible near the right edge of the pictures. It seems to come from a dead pixel. I also seem to have several dead pixels on the sensor, which for themselves don't bug me at all, but this line is visible even when resizing to web size, and probably will be in prints.

 

Sample picture #1: Resized ISO 2500 b&w shot.

L1113556-700.jpg

 

Sample picture #2: 100% crop from above.

L1113556c700.jpg

 

I'd love to get rid of this, but I fear that if I send the camera in, they will replace the sensor and charge me big time, as the camera hasn't got any warranty left.

 

Any ideas? I'd be grateful for any help.

Link to post
Share on other sites

Is that really true, Jaap? I have exactly the same problem with my M8 (warranty ran out early last year, hot pixel + line defect appeared a few months ago) and the only reason I haven't yet sent it in is that I'm weighing cost vs. inconvenience.

 

If Leica is fixing these (whether by mapping or sensor replacement) without charge then it's going in!

 

I was hoping that a new firmware - if the M8 ever gets one - would allow the user to map out their own hot or dead pixels but I think that's very much wishful thinking. Actually, the pixel isn't so much of a problem - it's the associated line defect that is, for me, much more of an issue.

 

Regards,

Jason

Link to post
Share on other sites

It is true that I never saw any complaint of anybody paying - and they are replacing Digilux2 sensors free of charge - but make 100% sure by contacting them with a faulty image before you send in. Or send the camera in anyway, there is always the option of having it returned without repair if you don't like the estimate. I would be really surprised if Leica charged for such a defect. But use Solms, don't go through local channels and contact Customer Service beforehand.

Link to post
Share on other sites

It is true that I never saw any complaint of anybody paying - and they are replacing Digilux2 sensors free of charge - but make 100% sure by contacting them with a faulty image before you send in. Or send the camera in anyway, there is always the option of having it returned without repair if you don't like the estimate. I would be really surprised if Leica charged for such a defect. But use Solms, don't go through local channels and contact Customer Service beforehand.

 

I contacted CS an am waiting for a reply. In the meantime, I'm using this: Pixel Fixer | Hot pixel removal utility It's a great software that maps hot pixels and repairs them directly in the DNGs. Also, it repairs vertical or horizontals lines caused by hot pixels. Works good so far with my files.

Link to post
Share on other sites

Thanks Jaap - Solms it will be :)

 

About Pixel Fixer: I have been aware of this but one thing puts me off, which may or may not be justified. This utility seems to be very good from what I read, but it works by de-mosaicing, fixing and then re-writing to raw. The thing that bugs me (even though I've not yet tried it) is the fact that I really like the way C1 treats M8 DNGs but if they are first run through PF, I'm wondering whether the result would be as though PF had done the actual de-mosaic, rather than C1 from the initial raw. In other words, C1 just processes a file which has been written by the PF process, which includes a de-mosaic and a re-write and it might be slightly inferior. I guess the answer is to try it :)

Link to post
Share on other sites

Thanks Jaap - Solms it will be :)

 

About Pixel Fixer: I have been aware of this but one thing puts me off, which may or may not be justified. This utility seems to be very good from what I read, but it works by de-mosaicing, fixing and then re-writing to raw. The thing that bugs me (even though I've not yet tried it) is the fact that I really like the way C1 treats M8 DNGs but if they are first run through PF, I'm wondering whether the result would be as though PF had done the actual de-mosaic, rather than C1 from the initial raw. In other words, C1 just processes a file which has been written by the PF process, which includes a de-mosaic and a re-write and it might be slightly inferior. I guess the answer is to try it :)

 

You can tell the program to keep the original RAW as well, so there's no risk trying it :-) Also, I don't believe it actually demosaics the RAW data, as there would be no use in doing so. As I understand it, it reads the pixel information from the RAW file, repairs those that are specified as being defunct (which you do when setting the program up, either automatically or manually) and then rewrites the repaired pixel information into the RAW file. Demosaicing and then remosaicing would proably sacrifice a whole lot of iq.

Link to post
Share on other sites

Just got an Email from Leica, they estimate charging me € 120 for getting rid of the issue via mapping - so no free sensor changing here. I think I'm going to stick to PixelFixer unless more hot/dead pixels start showing up.

Link to post
Share on other sites

efix, I'm sure (and hope) you're right re PF. I had read it somewhere, that it de-mosaics and then reconstructs the raw data but, as with many "opinions" floating about on the Web, it's not necessarily technically correct.

 

Looks like it's PF for me as well, then, unless my M8 needs to go in for anything else. If these sensors / electronics didn't produce the line defects along with the hot pixels I wouldn't worry.

Link to post
Share on other sites

I thought that someone in the forum posted about sending an example image in to Leica, and receiving a 'patch' firmware file that mapped out the pixel....

David, I think that was Tim Ashley with an S2.

Link to post
Share on other sites

Just got an Email from Leica, they estimate charging me € 120 for getting rid of the issue via mapping - so no free sensor changing here. I think I'm going to stick to PixelFixer unless more hot/dead pixels start showing up.

 

That seems crazy to me, I fail to understand why the software used to map out a pixel shouldn't be freely available - or at least provided as a free online service to registered owners.

 

Maybe this really is some complex manual process... but given my experience with pixelfixer I very much doubt that Leica do anything more than run a file through some software to produce the mapping.

Link to post
Share on other sites

David, I didn't program either the M or the S bodies. But if Leica could do it for the M, you know they would. It would save them and us time and money.

 

You say all they do is run a file through a piece of software. Wowsers. And how do they then tell the camera to apply those corrections?

Link to post
Share on other sites

David, I didn't program either the M or the S bodies. But if Leica could do it for the M, you know they would. It would save them and us time and money.

 

You say all they do is run a file through a piece of software. Wowsers. And how do they then tell the camera to apply those corrections?

 

Upload a file the same way as they do the firmware. It's hard to imagine they do it any other way.

Of course, I could be wrong and their software engineers might have been daft enough to make the fix for an entirely predictable and common defect something that requires factory disassembly of the camera.

Link to post
Share on other sites

Archived

This topic is now archived and is closed to further replies.

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...