Very Strange Problem!----Some of frames are black in the movie generated from UE4' 'Level Sequence'

Hi Everyone,

Currently, I have found the ‘Particle Effect’ from Epic Game and would get a water drop, splash and ripple effect. But I got a very strange problem that-when I render a movie using ‘Level Sequence’ function in ‘Cinematics’ section, a strange problem exists: the video scene turn to bright gradually and then turn to dark gradually, then it turns to bright gradually again (it likes that the scene/particle system compiles again…) during the video sequence. I thought that it may be caused by ‘Eye Adaption’ function in UE4, but this strange problem still exists after disabling ‘Eye Adaption’ in UE4.

Could you please help me with this strange problem?

Many thanks.