Ambient light control

A control device for use in an ambient light control system for controlling ambient light entering a space through an opening, the control device comprising:

• an ambient light prediction unit for providing ambient light prediction values, wherein an ambient light prediction value is a prediction of an ambient light property at the opening,
• an ambient light adjusting unit for providing, at different ambient light adjusting time points, an ambient light adjusting signal depending on the ambient light prediction values for an upcoming ambient light prediction time period, wherein the ambient light adjusting unit is adapted to provide the ambient light adjusting signal at several ambient light adjusting time points, wherein the ambient light adjusting signal is adapted for use by an ambient light modifying element for modifying the entering of ambient light into the space through the opening wherein the ambient light adjusting signal at a current ambient light adjusting tine point is provided depending on the ambient light prediction values for the upcoming ambient light prediction time period, wherein the upcoming ambient light prediction time period is the tie period from the current ambient light adjusting time point until the next ambient light adjusting tie point.