750 nits (cd/m^2) does fall within the high brightness range but the sensor for the Spyder X2 Elite is tunes for optimal performance in standard lighting conditions. The Spyder X2 Ultra is tuned for calibration in a broader range of brightness levels, specifically beyond 400 nits (cd/m^2) (but performs equally as well as the Elite in lower ranges using one of the 4 other Display Technologies).