![Attenuators vignette Attenuators vignette](/files/live/sites/www/files/UsersAndScience/Experiments/EMD/ID28/BeamlineLayout/OH1/attenuators_vignette.jpg)
The system consists of three racks, each equipped with 4 different absorption filters. They can be moved into the x-ray beam in order to cut the low-energy part of the undulator spectrum (typically the first and second harmonics). In practice, they are never utilised.