mobile

I have had this problem ever since I got my Nexus 5, but I went rooted short time ago and want to solve it once and for all ... if possible. The problem is that even when in the evening the brightness it at its minimum, the screen is still too bright for my taste. I have been using Screen Filter for a while and it does the job, I have been wondering if I could change the value of some parameter in some system file that would allow me to dim the screen even more. Any ideas if this is possible and, if yes, can you help me find that file?