For one pixel column, info readout shows pixel values of pixel to the left instead of true ones depending on zoom level, but x coordinate is correct. Setup: Photoshop CC 2015, Macbook Pro 15" with Retina display, PS window on second monitor (27", 1920x1080), eyedropper samples 1 pixel, CMYK image 45 x 33 px is a 1 pixel-per-patch version of the ECI2002 printer test chart, zoom to window (e.g. 2095%). Sometimes, one column (out of the 45) shows wrong values in the info palette: hard to notice, needs mouse-over the entire target. For power of 2 like 1600% zoom, things seem okay. On the retina display, it also seems okay for various zoom levels. The mapping of mouse coords to image pixels seems to be different for the displayed x y values and the actual selected pixels, where some kind of round-off error leads to the wrong position in the pixel image data. Probably new in CC 2015.