According to Ubisoft, the PS4 version of Assassin's Creed IV: Black Flag currently runs at 900p resolution, but an upcoming patch will enable 1080p output.
As Ubisoft communications manager Gary Steinman explains, 900p is upscaled to 1080p in the game's current state, but the patch, "available shortly after releases," ups the ante to native 1080p.
But why wasn't 1080p supported to begin with? Apparently, 900p enabled the team to ship Assassin's Creed IV on Day One with a framerate that never dips below 30 fps. With the additional time afforded by shipping at 900p, Ubisoft has worked out how to boost the game to 1080p on PS4 without making framerate sacrifices.
The new title update will also introduce an anti-aliasing technique for an extra layer of clarity on fine details like, for example, the ropes on a ship.
For more on Assassin's Creed IV, read our review of the PS3 version and stay tuned for our explanation of the next-gen difference.
Thanks, Game Informer.