[phenixbb] sharp rise of R-free in resolution bins

Hello everyone, I am refining a structure at 2.3 A resolution. R-work/R-free is 26/31 and is not reducing further. When I looked into the resolution bin, I notices a sharp rise of R-free between resolution range 2.5-2.6 A (marked in figure below). However R-work is fine. I am doubtful of reducing the resolution to 2.5 A or lower. Please suggest me your opinion. Your words will be highly appreciated. With regards, Bishal Singh PhD Student University of Heidelberg, Germany