Define 2 new image styles:
Modify the field featured image in news content type:
- Set max and min dimensions to 1214x320 pixel (i.e. the image must exactly have these dimensions)
- Change help text for featured image to explain, that we need the correct dimensiones
- Change the preview image to style w300x80 to get a better feeling for the result
Change the image style for featured image in the view frontpage slideshow to w1214x320.