 The Blinn-Phong differs from the Phong illumination model, as the Blinn-Phong model uses the vector normal to the surface of the object and halfway between the light source and the viewer.This model is used in order to have accurate specular lighting and reduced computation time.The process takes less time because finding the reflected light vector's direction is a more involved computation than calculating the halfway normal vector .While this is similar to the Phong model, it produces different visual results, and the specular reflection exponent or shininess might need modification in order to produce a similar specular reflection.