I've been looking at some 3W LEDs and I'm wondering where the 3W power rating is derived from? Using the absolute maximum forward current of 700mA and the max Vf of 3.5v i'm only calculating 2.45W and that is for a white LED with a high Vf. For a yellow LED with the same 3W power rating and a Vf of 2.6v i'm only calculating 1.82W. Those were calculated with the absolute maximum forward current. Using a forward current of 350mA which is what the wavelengths were anylized at, my calculated power outputs are halved. Are the power ratings just a class of LEDs such as anything grater than 1W and less than 3W is considered a 3W LED? It feels like i'm missing something here. Also, how much does the peak and dominant wavelenght of an LED shift when the forward current changes from say the 350mA used to calculate the wavelength and the 700mA absolute maximum forward current?