A bank angle of a vehicle can be accurately calculated using yaw axis data and roll axis data, and based on the calculated bank angle, vehicle illumination optics can be controlled to maintain a pattern of distributed light from the illumination optics to be generally horizontal. The calculated bank angle may be zeroed when the yaw axis data equals zero. The improved pattern of distributed light from the illumination optics illuminates a more natural field of view for the vehicle driver during a bank.