iview

I have resized the iview to 976×441 but the image, even if it is 976×441, it gets automatically reduced to 720×325. It is resized somehow through the image and not through stretching or shrinking. the location is “http:// blah blah.Image-720×325.png”. is it something that can be changed to display the image itself instead of a modified version? The image when I uploaded it was the 946×441.
I wrote background-size: 100%; in the css and it did fit the whole iview slider, but it started as the smaller version then snaps to full.

The reason I made it bigger is because I wanted the slider to be in the center of the page under the menu and above the main posts and the sidebar.

Thanks