The apparatus and methods herein provide quantitatively controllable light sources and expanded dynamic range endoscopy systems that can improve the quality of images and the ability of users to distinguish desired features when viewing tissues by providing methods and apparatus that improve the dynamic range of images from endoscopes, in particular for example with endoscopes that have dynamic range limited because of small image sensors and small pixel electron well capacity, and other optical system constraints. The apparatus and methods herein, for example, combine light sources with quantitatively variable spectral output and quantitatively variable wavelength dependent intensity distribution with image sensors and controllers to create an expanded dynamic range endoscopy system. By digitally combining illumination data from the digitally controllable light source with the digital image data from the image sensor the system synthesizes expanded dynamic range images whose dynamic range exceeds the dynamic range of the image sensor alone thus providing greatly enhanced information content in the acquired images.