Abnormal sparkling pixels in Canon 6D

Started by iaburn, December 20, 2023, 11:48:22 PM

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Hi, while recording some videos at relatively high ISOs, I found strange sparkling pixels of multiple colors, but not the usual noise, more like Christmas lights. The dual ISO clips have no weird pixels at all...
Anyone knows why is that happening? Here some examples to download: https://mega.nz/file/k1ECGAjQ#-pE4rPSMhIM9yo3t032dFHbKnGpy6nj1eRjn7IXQAy4



Those are hot/cold pixels, very normal when using high iso. (iso 3200 and higher probably).
Can be fixed in most raw photo/video software, search for hot/cold pixel fix.

MLVapp also has an option to fix this, it's called: Fix bad pixels.
It's Off by default, but the options auto or force fix most of dancing colorfull pixels in your samples.
For further cleaning in MLVapp, you may want to use chroma smoothing, 2x2 or more aggresive 5x5 setting.

Furthermore, you can reduce those in camera also quitte a bit for future recordings by doing a hot/dead pixel mapping one your camera.
Google for:hot/dead pixel remap canon dslr
Helped a lot with my 6d. Before doing the sensor cleaning without a lens attached and a body cap on, I warmed up the sensor by using iso 6400 in video mode for a few minutes.


Are you sure that these are hot pixels? They are only in some specific elements of the image, like palm trees for example, and the rest of the image is totally clean.
Maybe you are right, but I saw hot pixels before with high ISOs in other cameras, and the distribution pattern was more uniform and they were not following elements on the image.
I also cannot map them because they move around... quite strange


I call them hot/cold pixels, but they aren't indeed the type that are stuck forever. So it's not the same as a permanent hot/cold pixel which would show up at the same spot in all of your photos.
These hot/cold pixels are dancing around the frame and show up when using high iso on a low light scenery.
I took a closer look at your files, and the sparkling pixels show that either one of the green channels has a value of zero (so at the moment of recording, in that particular frame it was temporarily a cold pixel in the green channel).
It also happens in the dark area's but there the other pixels have values near zero, so it won't show up as a weird color.

For as far as I know, this is very common for all canon DSLR's with magic lantern raw video. Mostly it can be fixed by using hot/cold pixel fix in your raw editor (for example MLVapp with bad pixel fix)
What really helped reduce these for me is the dead pixel remapping (automated by your Canon DSLR, less then 5 minutes of work)

Take the lens of your camera and put the body cap on the camera.
And perform a manual sensor cleaning in the canon menu and wait for a while(probably one minute) to turn your camera off.


I see... I'll try that, thanks a lot for the tips! :D