Coming back from holidays, all was well when comparing my iMac to the new BenQ SW270C. Until the auto update which occurred during the night. After the update I cannot trust what I am seeing on my iMac 27” 5K. Color and contrast are washed out, even the icons in the dock are not as before. Glad you pointed out where this is happening. Not sure there is an easy fix, as I am now chasing around with all monitors to get a color match even close. On 13 Aug 2019, at 05:21, William Hollingworth via colorsync-users <colorsync-users@lists.apple.com> wrote: I'm starting to get reports of a severe banding problem that seems to be related to the recent macOS 10.14.6 update which includes some (unknown) changes to ColorSync. I've duplicated this and what I'm seeing is that when a display profile has the r/g/bTRC "curv" tag encoded as a "simple gamma" value rather than an array of points (typically 256), then there can be a big luminance discontinuity between level RGB=0 and RGB=1 - depending on the gamma value. I'm using a simple grayscale test image in the Preview app. The canned "Adobe RGB (1998)" profile encodes the 2.2 gamma as a "simple gamma" and this issue is evident when selected as a display profile. However the "Generic RGB Profile" encodes gamma 1.8 this way also but the discontinuity isn't very obvious. So higher gamma values make this more obvious. Re-encoding the profile's response curve as an array of points instead of a single "simple gamma" value seems to avoid the issue. However it was perfectly OK in previous macOS versions. Is anyone else experiencing this issue? It looks like X-Rite encode their TRCs as an array of points regardless, so probably most people won't see it. Anyone at Apple aware of this? Thanks Will Hollingworth Neil Snape