Banishers: Ghosts of New Eden – How to Enable HDR with Special-K

Download Special-K (https://sk-data.special-k.info/SpecialK.exe) and install it.

Open the folder “Steam\steamapps\common\Banishers Ghosts of New Eden\Engine\Plugins\NVidiaDLSS\Streamline\Binaries\ThirdParty\Win64” using your file manager.
Replace the “sl.interposer.dll” file with the one provided by Special-K (https://sk-data.special-k.info/misc/SK_Streamline-2_0_0.7z) as explained here: https://wiki.special-k.info/Compatibility/Streamline, and also remove or rename the “sl.dlss_g.dll” file (this will disable DLSS frame generation for the users of RTX40xx).

Launch Special-K and launch Banishers through it.

Open the Special-K configuration in-game by hitting Ctrl+Shift+Backspace. Enable HDR there (via HDR (in the top bar)->HDR Setup->scRGB HDR”). You might need to press “Alt-Enter” a few times and/or change “Windowed” to “Full Screen” in game’s settings for it to work.

I suggest using “SDR->HDR passthrough” option in Special-K HDR Setup settings, as “Native HDR10” one doesn’t produce good results in my opinion. I suggest enabling “Perceptual Boost” and setting “Brightness scale” to max, but otherwise the default settings seem to be fine. You can fiddle with other options, but I found that the default values worked the best for me.

Here is the general guide (not specialized to this game in particular) on using the Special-K HDR function on Special-K wiki:
https://wiki.special-k.info/en/HDR/Retrofit