>>4476481NTA.
1/8 is weak and subtle. It's difficult to find differences over a normal UV filter unless you're shooting brilliant points of light or high contrast scenes, and even then it's still subtle af.
1/4 still isn't strong per se, but tends to strike a happy medium without making things look creamy and low contrast.
But, the only mist filter I use nowadays is my 1/2 strength because I like that strong look, and if I'm not getting that obvious and deliberate low contrast look, I may as well take the filters off and shoot for max IQ. That's just how I do it though, 1/4 may be better for you.