How do I make all landing lights less bright on runway?

Hi All,All of my aircraft's landing lights are way too bright on the runway...almost a whitewash next to the aircraft external views and VC.Is there a global way I can dim the .BMP effect to soften the brightness of the landing lights, is it the spotlight.bmp??And how would I do it, or is there a freeware download for a less bright .BMP??Many thanks in advance.....