Windows Phone 7 users started noticing last week that after receiving all available updates, their phones didn’t look quite as pretty as they used to. The updates apparently decreased the bit depth used to display images, downgrading output to 16-bit and resulting in “banding” artifacts appearing in pictures with smooth color gradients. Although it’s not yet accessible to all users, there’s now a WIP fix available for those able to edit their phones’ registry, letting you customize bit depth settings.
The biggest caveat is that you’ll need a developer-unlocked phone in order to make these registry tweaks, and with no ChevronWP7 anymore, many users are going to be out of luck for now. After some experimentation over what values to modify, a group of users on the XDA-Developers forum have found good success with:
HKLMDriversDisplayPrimaryPrimBPP dword 32
HKLMDriversDisplayPrimarybpp dword 32
HKLMDriversDisplayPrimaryPanelBPP dword 24
Those values at the end of each line represent bit depth, changing them back from 16. Some users have noted during their tests modifying these values that pushing things too high can decrease smartphone performance; the updates lowering them seem to have done so in an effort to extract more speed from the devices.
This isn’t a 100% fix, as you may still notice banding in some parts of the OS, but it’s a start. The best option might be to offer a user-configurable display setting for making the adjustments yourself, trading speed for looks. What do you think, Microsoft?