How to Use Site for Image Optimization:
All images are presented at full resolution. To have Internet Explorer automatically size the image to your screen size, use: Tools-Options-Advanced and scroll down to multimedia. Check "Enable Automatic Image Resizing". This will allow you to view the whole image and then zoom in to see it at full resolution.
Fitting image to fullscreen:
Use F11 to toggle to full display. Hit F11 a second time to exit full screen mode.