Black concrete texture issue with lighting

Hello, I'm working on a massive project in the nether. It like a lot of black concrete because i want to use it as walls for a 129x129 area. The first wall was good and the black concrete gave the effect of the void. When i started on the second wall, i found an issue with the texture. It looks very strange with a lot of contrast. I dont think the contrast should be that high, at least it isnt that high in all the other concrete variants. (see screenshots) It has something to do with the brightness i think since if i put my brightness below 50% its not bad at all but at 100%, the contrast is really high.

To reproduce it:
1. Go to the nether
2. Place a block of black concrete where there is no light source like lava.
3. Turn you brightness first to 50% (when the texture is correct)
4. Now turn it to 100% (when its not correct)
5. Done.