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Removing Hot Pixels directly in BMPC4K camera WoW!!!

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  • Removing Hot Pixels directly in BMPC4K camera WoW!!!

    http://www.schweinert.com/blog/files...23958e-55.html



    After shooting some footage with my new Blackmagic Production Camera 4K I've noticed some unpleasant white hot pixels all over the image. They showed up in lowlight but also in correctly exposed (untouched) daylight clips. Somewhere in an old post I've read that a firmware down- & upgrade may help but there was no confirmation by anyone. Don't know but seems like it was forgotten. Anyway for others with the same problem try it. For me it worked really good!

    Blackmagic Production Camera 4K (don't know if that works with other BMD cameras too)
    This is exactly what I've done:

    1. Take out the SSD and take off the lens.
    2. Put the Camera Body Cap on.
    3. Connect the power adapter to the camera.
    2. Downgrade the Firmware to 1.8
    3. Upgrade the Firmware to 1.9.8

    See the before & after 1:1 crop above. I don't know if the camera triggers an undocumented internal pixel mapping but the hot pixels are gone and the overall image is now much better! Thats awesome - though I don't know how long it will stay that way. I will see :-)

    If that didn't worked for you then there is still an easy workaround directly in DaVinci Resolve:

    1. Create a node with a Power Window and resize it to 1.0 and set Soft1 to 0.00
    2. Zoom in and move the Power Window directly above the hot pixel.
    3. Got to the Blur Palette Effects and set the Radius of the Blur slider to 0.53
    4. If you positioned the Power Window directly above the hot pixel it should be gone now.
    5. If not try to reposition the Power Window.
    6. For each hot pixel create a new node then copy and paste the Power Window. Reposition it on the next hot pixel and so on ...
    7. Create a PowerGrade from the whole node structure and use it on other clips with hot pixels.

  • #2
    interesting

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    • #3
      Very interesting..

      Comment


      • #4
        Every time I see something like this I want a 4K more and more. Great research.

        Comment


        • #5
          Seems possible. Red for example is recommending a black shading (which is something like hot pixel mapping) after each firmware upgrade. Maybe BM rolled this into the upgrade? Could explain the flickering right after installing new firmware.

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          • #6
            has anyone noticed this in the BMPCC? If you already have 1.8 do you just upgrade to 1.9.8 to get this supposed black-shade in camera?

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            • #7
              danielschweinert

              Maybe it just went cool down after your update? There was a lot discussion about that. When BMD cameras get hot then they produce more fpn with stuck pixels. Try to make a 40 min running test.

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              • #8
                Today I shot again a couple of clips and everything is fine. If I compare the clips before and now it's a difference between night and day.

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                • #9
                  If the camera is doing some sort of black shading after a firmware update having the body cap on would be critical, broadcast cameras close the iris automatically, because auto black shading needs well, black. Another compelling argument for more thorough firmware documentation. Thanks.

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                  • #10
                    I tried the downgrade and upgrade on the pocket. It did not work however I did not remove the sd card during the down up. I will try it again later today removing the sd card.

                    At this point I have to either shoot at ISO 200 or go to pixel mapping in Resolve. (or exchange the camera).

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                    • #11
                      Don't do it boys. Now I have 2x more noise than it was
                      Andrew Bell
                      Blackmagic Production 4K Camera
                      https://www.youtube.com/user/reklama4demo

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                      • #12


                        I have no idea how to return my previous results.
                        Andrew Bell
                        Blackmagic Production 4K Camera
                        https://www.youtube.com/user/reklama4demo

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                        • #13
                          Update. Picture below is the result of cameraheating. Not the fw update. The more camera works the more heat it generates. When camera warmer the more noise it generates! So my picture basically indicates camera heat vs noise progress.
                          First line of pictures taken at moment of power on.
                          Second line is about a half of hour of running.
                          And the bottom line - about a hour of camera work.
                          Andrew Bell
                          Blackmagic Production 4K Camera
                          https://www.youtube.com/user/reklama4demo

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                          • #14
                            Now when camera cool down it shows the first line results.

                            P.S. Sorry for a lot of messages - just can't edit my previous posts (blame the IE11!).
                            Andrew Bell
                            Blackmagic Production 4K Camera
                            https://www.youtube.com/user/reklama4demo

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                            • #15
                              I did the sequence again on the pocket with the SD card out. No difference.

                              As an fyi what set this off is I was testing the pocket's boundaries and monitoring off of an uncalibrated 58" plasma (because it was there) lit chiaroscuro. And of course I got hot pixels in... my black shirt when I walked through shadows in front of the camera. Imagine that!

                              Which set me off about hot pixels in the correctly exposed areas.

                              After all of this I looked at my 1.8 and 1.9.8 tests on calibrated monitors and found I really only have 1 annoying hot pixel near the lower 1/3 in the middle 1/3 of the sensor which can be mapped out in post. Or I can remember to shoot at ISO 200 with this set up or use a different camera.

                              Anyway it would be nice to be able to pixel map out odd pixels in camera but it seems like a bit of a stretch for the price of the camera.

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