This beta as with the last continues to incorrectly present images and colours. The same PDF file opened in Adobe Acrobat opens perfectly with all colors correctly presented. I have submitted bug notices for this in the previous build and now this one.
A black object in Preview appears Grey. In Adobe Acrobat it's black. Dark colours are now patchy and light.
Take a screen shot from Mac of either Preview and the images are low res and new colours that were not in the original PDF are now visible.