On a Mac, open your site in a web browser. You can do a screen capture by pressing "command-shift-3" or to capture a selected area "command-shift-4" then draw a marque around your browser window. A graphic called Picture1 (or other number) will appear on your desktop. Double clicking it will launch Acrobat, but if you launch Photoshop and pull down "file open" you can open it in Photoshop to edit it, crop, splice together seperate images, etc.