thank you , i have reviewed my saves , it really does ,sorry!
but in an other way , it means , the game doesnt show the Effect of Illumination well!
1. the shadow situation is really rare , most of the scenes are very good illumnated , under Sun or Unter Lighting, so we dont face the Illumination Situation much.
2. the Negative Effects of the shadow is so small , i never noticed it , i can hit it even with my priest.
3. the game should tell us , how much is the negative effect , so that we can make a tactical Thought , only a tool tip to mention it is not cool, and i have igored this Negative effects all the time throught the gameplay , and it made me no problem , that is not right ! it should make Combat difficult,if i ignore a cricital factor.

so i would like to suggest : decrease the Illumination Range of the Light source , show the detail Negative effect on the Tooltip, and i hope this negative effect is a important issue for Rang Attackers.