The term ‘Duo’ is given to a wide range of double sided photographic papers of professional premium quality. Most photo papers regardless of size are coated on one side to accommodate the ink making it impossible to print anything on the non-coated side. In some cases the non-coated side can be used to accommodate simple text printing, but never ever a high quality image.
Single sided coating is the most common type of photographic paper coating due to lower costs of production and the nature of how prints are traditionally displayed. For example, desk mount photos, wall mount photos, pocket size traditional photo album (6×4” and 7×5”) and other manners of photo paper uses are single sided as they are viewed directly and there is little need for duo sided capability.
Duo sided photo papers (or two sided for a better word) are essential when you are looking to print an image on both sides of the paper such as when making a brochure, invitations, wedding or luxurious binded photo album books and other applications when an image is required on both sided of the media. Unless the photo paper which you are intending to purchase clearly mentions that reversed printing is possible, you can safely assume otherwise. Papers of both sides printing capabilities will include terms such as Duo, Double-Sided, Two-Sided and other similar abbreviations in their description.
Image by flickr under cc license