Sometimes, depending on the image, ACR (v.188.8.131.52) will push the exposure slider up while simultaneously pulling the brightness slider down when I elect to use the auto button. The result often creates odd and unrealistic tonalities even to the point of making the image appear overexposed in the mid-range. From what I can tell, the histogram is only subtly altered. What's the logic behind this behavior in the auto-function? I could provide .png images if anyone's interested in taking a look.