# Why is there a distinct boundary between light and dark in the scene after using rect/strip lights?

<figure class="doc-image doc-image--stack">

![image](https://docs-static.d5render.com/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces/-MjbN1iGmN_HBnj_fyU9/uploads/2DSXd2TucvBY5WSbt7OT/image.png)

<figcaption>The light overlaps with the top surface</figcaption>

</figure>

This phenomenon may occur if the rect/strip light overlaps with the model; please adjust the position of the light source slightly to get the normal effect.

<figure class="doc-image doc-image--stack">

![image](https://docs-static.d5render.com/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces/-MjbN1iGmN_HBnj_fyU9/uploads/h4zkdMMUHZC04xQWXXKm/image.png)

<figcaption>The light moved down slightly, do not overlap with model</figcaption>

</figure>