A method includes modifying values of image data of a first image of an object, the first image taken by a user using a user equipment. The modifying is performed to map one or more color characteristics of one or more color components of the user equipment to corresponding one or more color characteristics for the one or more color components of a reference device. The modifying creates a modified image. On the user equipment, comparisons are performed between the modified image and a number of second images of objects taken by the reference device. Apparatus and program products are also disclosed. Additionally, a user interface is disclosed that provides for training a device model that is used during the mapping.