Revolution Slider: Width

Hi there,

There is always a small border between the screen and my image, when I add a main background image in my revolution slider. My settings in “main background” are:

image source size: original size
background fit: cover
background position: center-center
background repeat: no repeat

Is there a possibility to shift the background image, like i can do it with a imaga layer picture?

Thank you for your reply!