<p>Incident and reflective meters come at the result from two different ways. The reflective takes what it reads and provides a result that places those tones at the 13% or 18% target. Incident meters are keyed to the highlights. What the meter sees is a highlight within the light falling on it. It then adjusts the exposure a (predetermined) couple of stops to achieve a keyed midtone. There is no reason they will be the same result</p>