Hot pixel on DMR, how to fix?

[LVSBB6]

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I notice there is a hot pixel (red) on the picture with DMR when doing shutter speed at 1s or slower, does anyone have the same issue?

 

I tend to do a lot of night shooting with long exposure, these red pixels can easily be seen in every picture.

 

After hearing up that DMR can no longer be repairable, what can done to get rid of the hot pixels?

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[krandall]

I haven't had a hot pixel on my Leica, but I did have one on my first Canon SLR. My understanding is that there ISN'T really anything you can do about the pixel inside the camera. But if it's a single pixel, it should be an easy fix with the Healing Brush in Photoshop.

[wildlightphoto]

... After hearing up that DMR can no longer be repairable..

 

I wish that people wouldn't repeat this unless they have substantial evidence of its veracity. Several owners I know of have recently gotten DMR repairs.

[stuny]

Doug is correct. My DMR is in for repair right now and I expect to have it back this week.

[LVSBB6]

Is the repair sensor related?

 

Doug is correct. My DMR is in for repair right now and I expect to have it back this week.

[beewee]

There's a simple fix for this in Photoshop by creating the following set of actions:

 

1) Pin point exactly which pixel is hot and make a selection for that pixel in the uncropped image

2) Create a custom filter with the following window:

 

1 1 1

1 0 1

1 1 1

 

3) Set the scale to 8

 

4) Apply the filter to the selected pixel.

 

What this does is for that particular hot pixel, it will ignore the values in the hot pixel and replace it with the average value from the surrounding pixels. This is the same method used for calibrating new sensors to remove hot pixels. Otherwise, it would be incredible expensive to source sensors which are 100% free of dead/hot/stuck pixels. This method also works for stuck/dead rows/columns of pixels.

[LVSBB6]

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Is hot pixels dust related? would sensor cleaning help at all?

[beewee]

Is hot pixels dust related? would sensor cleaning help at all?

 

Nope. Hot/dead/stuck pixels are defects on the sensor and can be caused defective gates, voltage leaks and other defects on the silicon sensor. They exist on even the most expensive medium format backs but are usually calibrated out (same method as shown) on firmware so the user doesn't actually see them but they are there.

[LVSBB6]

Attached are two jpeg pictures I took with 12s exposure, one with lens cap covered, the other is night view shots. You can see blue/red/green dots scattered around the pictures.

 

I noticed the hot pixel started to appear at 1s or longer exposure, more random hot pixel dots would appear as the exposure time is increased.

 

Some ppl said hot pixels exists on every sensor, so I tried doing a 60s exposure on my Olympus E3 with lens cap covered, not a single hot pixel appeared in the picture

 

Is it time to send the DMR back to Leica for fix/service? is your DMR behaving the same way under long exposure?

 

 

[jaapv]

You should send it in; Leica will probably remap the sensor.

[Thomas Glasgow]

Hi,

 

I also had these results, I thought it was a pixel problem, however it was sensor dust, these marks don't show up on faster brighter exposures where the light passes through the specs. clean the sensor with the right kit and test it, we can never get sensors 100% clean so you might get the same problem with a different amount and pattern, at least you will know its not a sensor malfunction.

 

Hope you resolved this one.

 

Thomas