Unreal Engine 4.15 Preview

Did something change with the lighting in the 4.15 preview? Everything seems a little bit darker to me. I think my post processor is making the differences more apparent but it’s still noticeable with it turned off. Here are 2 comparison screenshots between 4.14 and 4.15, one with my post processor on and one with it off: http://imgur.com/a/xpni5