images not same size as set

i have the images at a size of 600x600 and also the same within the admin settngs, yet they are not 600x600 square!

please help?

you use a Custom Responsive theme. And since it act's responsive, it automatically shrinks your images, to a size, matching visually sizewise with the rest of the Page. If it would not, it would BREAK your Setup, and no longer display the entire page in the 'given' browser screen size.
That's all!
Ernie