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

<div align="center"><figure><img src="https://3611830798-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F-MjbN1iGmN_HBnj_fyU9%2Fuploads%2F2DSXd2TucvBY5WSbt7OT%2Fimage.png?alt=media&#x26;token=778b4ffd-1918-49e6-b8c4-f0d4e5e7ffc9" alt="" width="563"><figcaption><p>the light overlaps with the top surface</p></figcaption></figure></div>

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.

<div align="center"><figure><img src="https://3611830798-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F-MjbN1iGmN_HBnj_fyU9%2Fuploads%2Fh4zkdMMUHZC04xQWXXKm%2Fimage.png?alt=media&#x26;token=9d88c1c4-4a2b-4355-9bad-a1f1596632fd" alt="" width="563"><figcaption><p>the light moved down slightly,  do not overlap with model</p></figcaption></figure></div>