Use RawTherapee to deal with laser damaged camera sensors

Camera sensors are, in general, more susceptible to laser damage than the human eye. Mirrorless cameras with no mirror to protect the sensor are more exposed.

For details about damage thresholds, see ILDA.

If your camera sensor is damaged by laser the repair cost may be the same as getting a similar, used camera. If the laser damage is limited to a line or some few dots you may just map them out in post.

RawTherapee has this feature. You create a text file and write down all the positions of the bad pixels. The name of the text file should be the same as your camera model name in RawTherapee.

Canon EOS 5D IV sample

In the RawTherapee manual the following is written:

RawTherapee can correct a list of bad pixels (pixels that are always black or white or stuck at one color) for your particular camera model. To do this, you need to write a text file with the absolute raw coordinates of these pixels: each line specifies a pixel with x<space>y<return> positions.

The name of the text file should be:

Canon EOS 5D Mark IV.badpixels

Because RawTherapee is cropping the raw file a little bit, 4 pixels for Bayer-sensor and 7 pixels for X-Trans-sensors (Fujifilm) you need to write an offset in the first line in the text file. In this case with Canon EOS 5D IV that uses Bayer-sensor you will ned to write 4 at the first line. After that you just write down the positions of the bad pixels.

It may be easier for you if you turn off White Balance.

Open the raw file in RawTherapee, choose a neutral profile. In Demosaicing, choose Mono or None. You see the coordinates to the left as x and y. Write them down in the text file.

Now try if it works for you. Save the text file. Make sure it is in the Darkframes directory, see the picture below. Restart RawTherapee every time you update the text file.

Raw samples from the Dpreview user ash92. Bad pixel list for his 5D IV included.

Tips and tricks

Take raw files of something that is magenta to get a more even tone between the pixels. Easier when you turn White Balance off and use None as demosaicing method. More details of how to take the picture here.

If you have lines or columns damaged due to laser, then you can use Excel or LibreOffice to generate a list in a few seconds. Write down the two first coordinates and then use the mouse pointer to drag down the whole list.