Getting only Red channel when opening DNG RAW images taken with Pixel 4 XL

When I open a RAW photo in DNG format taken with my Pixel 4 XL phone, Siril displays only the Red channel in the B&W channel window.

Does Siril fully support the DNG format? Is it skipping the Green and Blue channels? Are the channels missing from the DNG files Pixel phones generate?

I’m using Siril 0.9.10 on Debian Buster under Crostini, the Chrome OS Linux container. I open DNG files with File > Open > RAW DSLR Camera Files. I attach a sample DNG file, a photo of an approximately 30° wide star field centered roughly around v And and M31, taken at 2X optical zoom with my Pixel 4 XL.

IMG_20200820_222259.dng (8.2 MB)

The sensor has a Bayer filter matrix. What is recorded in pictures is the amount of light that comes through each filter. To get the colours, they have to be interpolated, this operation is called demosaicing. Demosaicing is not made by default in siril because preprocessing must be done before doing it. You can force it by using the conversion and checking the demosaicing option.

The version you are using is also very old and you may want to update, I’m don’t know what Crostini is and if it is possible with it though.

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@vinvin Thank you, the conversion with demosaicing did the trick.

Crostini is the subsystem of Google’s Chrome OS operating system of Chromebooks and related devices that allows to run a Linux distro in a container alongside Chrome OS. By default Crostini runs Debian, currently Buster. I attached a screenshot of Siril on my Chromebox (a desktop computer with a mini PC form factor running Chrome OS).

I installed Siril with sudo apt get install siril, here’s my /etc/apt/sources.list:

deb buster main
deb buster/updates main

I guess the official Debian repo doesn’t track Siril’s development closely.

Yes it does. I was just in vacation :slight_smile:

I’ve installed Siril 0.9.12 as explained in the Debian-related documentation.

@lock042 Thanks, no problem. I’ll be happy to switch back to the official Debian repo.

Debian stable only gets the version that is available at the date of release, unless there is a security concern it does not get updated. Releases happen about every two years.
But indeed we make unofficial packages ourselves for all debian versions in general.

I track whatever Debian stable version comes with Crostini, currently Buster. Do you recommend sticking with Debian’s repo or installing your unofficial .deb packages? I seem to understand the latter are more frequent.

Our unofficial packages are updated more often but it’s not automatic.

Thanks, I’ve seen Siril has a handy Help > Check For Updates option.