Microsoft has confirmed that color banding and resolution issues HTC HD7 and HTC Trophy owners experienced after installing the recent Windows Phone 7 NoDo update was intentionally provoked, blaming HTC for stepping outside of the strict specification rules for the platform. According to a Microsoft support team member, HTC granted the two smartphones 32-bit color depth support, and NoDo switched that to the mandated 16-bit; in the process it triggered visual glitchiness and banding, a side-effect that Microsoft reckons users shouldn't actually see.
"When HTC launched the HD7 and Trophy they upgraded the color depth to 32 bit, which was outside of Microsoft’s design requirements of 16bit. Microsoft implemented the design standards to help ensure the best possible and consistent experience for all customers on all Windows Phones. To continue to deliver a stable and consistent customer experience, HTC returned the devices to the 16 bit design requirements as part of the March (7.0.7390) update.
The color palette change should not make a noticeable change to most customers experience on their Windows Phone 7. Microsoft’s goal is to ensure that the device is performing as optimally as possible – and as always their engineering teams continue to investigate the opportunities for future improvements." Aled T, Microsot Support
As you might expect, that didn't go down well with HD7 and Trophy owners. "I think it makes a BIG difference. Everywhere" Trophy user Santiago Castelo suggests. "Apps, games, photos, videos, bing background, lockscreen, marketplace... it's everywhere, and in some places (like the marketplace shots) it looks terrible."
Castelo has shared a gallery of shots (one of which is above) showing just how his phone now displays various images and how they're meant to look. It seems Microsoft turned off 32-bit support but didn't turn on dithering, leaving the handsets looking distinctly underwhelming.