Images with a green border are the high-resolution, and images with the red border are the standard-resolution.
Below are some examples of high-resolution and standard-resolution images so you can compare their quality side-by-side. This page does not use javascript to change the image's src, but instead has hard coded src values for the different resolutions for each image.
Photo by Honza Groh
Photo by Kallerna
Photo by Joi Ito
Photo by Softeis
Photo by Roger McLassus
Born to the West (Paramount Pictures)