HP promises a brightness value of 1000 cd/m² for its EliteBooks with SureView screens. The recently reviewed HP EliteBook x260 830 G6 has an extremely bright screen – but it does not manage to hit the brightness value that the manufacturer promises.
https://www.notebookcheck.net/HP-EliteBook-x360-830-G6-HP-laptop-does-not-deliver-its-promised-LCD-brightness.436952.0.html
It is said that the sureview fuction decreases the transparency of the screen cover, thus decreasing the brightness readout on external calibrator.