Hello hoolito,
The anti-aliasing is a software feature that helps smoothing between each print layer!
As explained here (Chitubox software): https://www.instructables.com/id/5-Settings-to-Improve-Your-SLADLPLCD-3D-Print-Qual/
And on this page, we’re talking about the Form 3 anti-aliasing (Yellow highlight)!
But I never figured out how to activate this feature in Preform!
I have a small PhotonS and this function is supported! I find it strange not to find it in Preform.