ENBSeries

Hey i'm making a Contrast effect and i'm using this equation : color.rgb = (color.rgb - 0.5) * Contrast + 0.5;. However, it's not really smooth and creates dark areas. Any idea of another smoother equation?

Maybe try non linear amount of shift, when near black and near white value is compressed. Something like the following code (check yourself for errors, i just give an idea):
float ContrastCurve = 1.0; //change this
float nonlinearcontrast = dot(color.rgb, 0.3333);
nonlinearcontrast = abs(nonlinearcontrast * 2.0 - 1.0);
nonlinearcontrast = saturate(1.0 - nonlinearcontrast);
nonlinearcontrast = pow(nonlinearcontrast, ContrastCurve);
color.rgb = (color.rgb - 0.5) * Contrast * nonlinearcontrast + 0.5;