A method of controlling an illumination device, said illumination device comprises a number of light sources arranged in at least a first group of light sources and in a second group of light sources, where said method comprises the step of: controlling said first group of light sources and said second group of light sources individually based on an input signal indicative of at least a first preprogrammed effect function and at least a second preprogrammed effect function and wherein said input signal is further indicative of a number of control parameters; wherein said first and second preprogrammed effect function being stored in a memory in said illumination device; wherein said method further comprises the step of activating the first and second preprogrammed effect functions at the same time, wherein when activating the first and second preprogrammed effect function at the same time, the step of controlling further comprises controlling the first and the second group of light sources based on a priority schema defining a relationship between said first preprogrammed effect function and said second preprogrammed effect function, wherein said priority schema is stored in the memory in said illumination device and comprises a number of priority rules defining how said first preprogrammed effect function and said second effect preprogrammed function must be executed in relation to each other in the case that a first output of the first preprogrammed effect function and a second output of the second preprogrammed effect function manipulate the same output parameter of the first and second light source; wherein, when activating the first and second preprogrammed effect function at the same time, the step of controlling further comprises controlling the first and the second group of light sources based on a synchronizing schema defining a relationship between the first preprogrammed effect function and the second preprogrammed effect function, wherein said synchronizing schema is stored in said memory and comprises a number of synchronizing functions defining how said first preprogrammed effect function and said second effect preprogrammed function must be execute in to relation to time and in relation to each other; wherein said priority schema comprises a look-up table and said step of controlling said number of light sources of the first and second group of light sources comprises the step of finding at least one of said priority rules in said look-up table based on said first preprogrammed effect function and said second preprogrammed effect function and basing the controlling of the first and the second group of light sources on the found priority rule. controlling said first group of light sources and said second group of light sources individually based on an input signal indicative of at least a first preprogrammed effect function and at least a second preprogrammed effect function and wherein said input signal is further indicative of a number of control parameters; wherein said first and second preprogrammed effect function being stored in a memory in said illumination device; wherein said method further comprises the step of activating the first and second preprogrammed effect functions at the same time, wherein when activating the first and second preprogrammed effect function at the same time, the step of controlling further comprises controlling the first and the second group of light sources based on a priority schema defining a relationship between said first preprogrammed effect function and said second preprogrammed effect function, wherein said priority schema is stored in the memory in said illumination device and comprises a number of priority rules defining how said first preprogrammed effect function and said second effect preprogrammed function must be executed in relation to each other in the case that a first output of the first preprogrammed effect function and a second output of the second preprogrammed effect function manipulate the same output parameter of the first and second light source; wherein, when activating the first and second preprogrammed effect function at the same time, the step of controlling further comprises controlling the first and the second group of light sources based on a synchronizing schema defining a relationship between the first preprogrammed effect function and the second preprogrammed effect function, wherein said synchronizing schema is stored in said memory and comprises a number of synchronizing functions defining how said first preprogrammed effect function and said second effect preprogrammed function must be execute in to relation to time and in relation to each other; wherein said priority schema comprises a look-up table and said step of controlling said number of light sources of the first and second group of light sources comprises the step of finding at least one of said priority rules in said look-up table based on said first preprogrammed effect function and said second preprogrammed effect function and basing the controlling of the first and the second group of light sources on the found priority rule.