Windows 8.1 Force a specific default lock screen image

Hi,

at the moment we are preparing the win 8.1 rollout in our environment.

Now we tried to customize the lock screen image.

There we are facing the issue that the image does not get correctly resized to different screen resolutions.

Therefore we are using a image with a resolution of 2160x1440 pixels.

Does anybody have an idear how tho fix this ?

Thanks in advanced,

Thomas