Media sizes

If we have 3 types of Webbook Width


why the max size of the images is bigger than the mx webbook width. Why we do not have a more optimiced size?

that´s now

and i´m thinking
if the book size wide is 832 . Why is not that size the maximun if we choose wide book size? or 688 if we choose the standart.

300 can be good as a medium image size, but 1024 is too big.

Fix it with a plugin