Photos app doesn't sync via itunes

I just noticed that with apple's new Photos app, when I plug in my phone and sync photos through itunes, new photos on my computer in the Photos program do not automatically sync to my iphone even though the "Sync Photos" box is checked. I had no trouble with this with the old iPhoto program. Is there a way to fix this without using icloud sync? I do not like icloud because it is too unreliable.