Wide banner images stretched over two columns

[tauren]

In default theme there was 3 banner images (width 1) and under them two wide. One (width 1) and one (width 2, stretched over two columns). I deleted them, and now I want add these wide images again, but I do not know how. If I add image with width 2, on site is this image smaller with width 1. It does not matter if I set hard image size or if image size is not set.

Width was 383px or 777px for wide image.

Thanks for reply.