Set header image focus to center or bottom

Hi there, I am using My Music Band Pro and experience some issues with header images. As a header image, I am using a wideshot photo of a group of people. On most (non-mobile-) viewports, their heads barely show as the image is cut off. The image focus seems to be at the top of the image (the top always shows, bottom or even middle is cropped). http://stage.diehamburgerklabautermaenner.de/ I need a way to set that focus to the center or the bottom. How could this be done?