highlights. Some slide films can have a Dmax close to 4.0d with proper exposure, and so can black-and-white negative film. Consumer-level flatbed photo scanners have a dynamic range in the 2.0–3.0 range, which can be inadequate for scanning all types of photographic film, as Dmax can be and often is between 3.0d and 4.0d with traditional black-and-white film. Color film compresses its 12 stops of a possible 16 stops (film latitude) into just 2.0d of space via the process of dye coupling and removal of all silver from the emulsion. Kodak Vision 3 has 18 stops. So, color negative film scans the easiest of all film types on the widest range of scanners. Because traditional black-and-white film retains the image creating silver after processing, density range can be almost twice that of color film. This makes scanning traditional black-and-white film more difficult and requires a scanner with at least a 3.6d dynamic range, but also a Dmax between 4.0d to 5.0d. High-end (photo lab) flatbed scanners can reach a dynamic range of 3.7, and Dmax around 4.0d. Dedicated film scanners have a dynamic range between 3.0d–4.0d. Office document scanners can have a dynamic range of less than 2.0d. Drum scanners have a dynamic range of 3.6–4.5. By combining full-color imagery with 3D models, modern hand-held scanners are able to completely reproduce objects electronically. The addition of 3D color printers enables accurate miniaturization of these objects, with applications across many industries and professions. For scanner apps, the scan quality is highly dependent on the quality of the phone camera and on the framing chosen by the user of the app. Computer connection Scans must virtually always be transferred from the scanner to a computer or information storage system for further processing or storage. There are two basic issues: (1) how the scanner is physically connected to the computer and (2) how the application retrieves the information from the scanner. Direct physical connection to a computer The file size of a scan can be up to about 100 megabytes for a (9"x11") (slightly larger than A4 paper) uncompressed 24-bit image. Scanned files must be transferred and stored. Scanners can generate this volume of data in a matter of seconds, making a fast connection desirable. Scanners communicate to their host computer using one of the following physical interfaces, listing roughly from slow to fast: Parallel port - Connecting through a parallel port is