Here is a real example of a recently completed assignment. The original image uploaded had been joined using Serif and was only 256Kb in size and pixel size was 626x2978.
Not a badly joined panorama but a little bit on the small size with an elongated shape and sky rather light and patchy. Max size to print was quoted 10x47cm. I presumed with those dimensions that it had been taken on a mobile phone as many of these have a panorama mode now. (you may not be surprised the iphone has an app for this!)