Bug in Matinee - Artefacts with Depth of Field (UE 4.7)

Hi,
I have serious problems with Depth of Field when I make movies with the Matinee Editor. In the viewport everything is ok. But after the rendering I have strange artefacts in the depth of field areas(like color banding) .
This must be bug because these artefacts only appear in the movie.

Best regards, Andreas