There are many ways to get the job done.. try various shaders

tonemap can help as well
... or maybe some shader to just increase contrast.
This is my preset but its not for retro mode:
place it where your DaggerfallUnity.exe is, and load it ingame in the Reshade
Here is the ReadMe Ive created for Dream Reshade users:
With retro mode - you most likely dont want the antialiasing... maybe not even sharpening, dunno, experiment... and try also different shaders, good luck
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Setting up ReShade:
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1)Start ReShade_Setup_4.8.2.exe
2) Click grey button "Click here to select a game and manage...."
3) Click "Browse"
4) Navigate to your "DaggerfallUnity.exe" (Game folder - example: "C:\GAMES\Daggerfall")
5) Click "DaggerfallUnity.exe" & than click "Open"
6) Select "Direct x 10/11/12"
7) Make sure "Standard effects" + "SweetFX by CeeJay" + !!! "Legacy standard effects" !!! are selected
Legacy standard are at the bottom of the list!
8) Click OK
9) Always "Select all" and click OK
DONE!
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Import the DREAM RESHADE preset:
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Copy "DREAM 2020 R3 - Prefer Looks.ini" + "DREAM 2020 R3 - Prefer Performance.ini" to
the same folder where you "DaggerfallUnity.exe" is located (for example "C:\GAMES\Daggerfall")
DONE!
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Load the DREAM Reshade preset in the game:
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Reshade starts automatically when you start the game, displaying info on the tab at top of the screen briefly.
1) Open the Reshade menu by pressing "Home" key - click "Skip tutorial"
2) At the top you can see "ReShadePreset" - Click it
3) Click on "DREAM 2020 R3 - Prefer Looks" (or Performance)
4) Click on "Select"
5) I suggest setting up ON/OFF key to "End" key (its under the "Home" key)
You can set it up in the "settings" - "general" - "effect toggle key"
DONE!
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RESHADE TROUBLESHOOTING:
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Fix for PCs where Reshade is crashing the game on startup:
rename dxgi.dll and dxgi.log to d3d11.dll and d3d11.log respectively.
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WHAT IS THE "DREAM RESHADE" ?
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Custom shaders specificaly tailored for Daggerfall Unity DREAM mod and mod presets.
Its very spartan and non intrusive while making the final picture more detailed, focused and clean.
Plus its light on you HW. My GTX970 and Ryzen 5 3600 CPU do the locked 60fps no problem.
IT USES THESE EFFECTS:
1) AdaptiveSharpen
2) SMAA
3) Tonemap
4 + 5) BloomAndLensFlares
6) EyeAdaptation
7)AmbientLight
1) Sharpens the textures and sprites, using Adaptive Sharpen
2) Injects SMAA antialiasing, which is superior to the game AA. (Dont use ingame AA in the "postprocessing" mod)
3) Tones the colors very slightly to create a nicer more pristine look
4) Adds a high quality Flare to the sun (Dont use Flare in the "Enahnced Sky" mod)
+ 5) Injects very subtle brightness bleeding effect tweaked to appear only at the sun borders and
similar areas like lights. This creates a more graphicaly advanced and moody lightning in many circumstances.
6) It uses soft eye adaptation, which brightnes the dark dungeons and darkens the brightest game areas dynamicaly
7) Uses very soft Ambient light, this is used to create more advanced light effects around sun and lights