I am working on an application for sharing a scanner. I have a webform for all the settings, a "Scan" button, and a "Preview" button. When the user press "Scan" nothing on the interface changes. A "Save As" window pops-up. But what should happen when the user press "Preview". I was thinking about a dialog window containing the scanned preview, but the images are usually too big (1248x1640 for example)?