You have two options when you want to want to make big prints of your photos. Either lower the dpi to obtain a larger print size and accept a loss of quality. Or try to interpolate up in size using Photoshop or another image editor, which can lead to artifacts and loss of sharpness.

SmartScale is a new Adobe Photoshop plug-in from Extensis that claims to be able to “Scale images up to 1600% with no discernable loss in printed quality”. You can preview different scaling options in real-time and refine the quality of your scaled image by controlling the overall sharpness, edge contrast and edge detail. At $199 it’s perhaps a little on the expensive side for home-users, and unfortunately there’s no trial version available to test it out.

Website: Extensis SmartScale

Website: Extensis