ABSTRACT
This chapter deals with the issues of digital file resolution, and two of thefirst questions everyone wants answered – how do you define it and just howbig a file do you really need? When we talk about resolution in photographic terms, we normally refer to the sharpness of the lens or fineness of the emulsion grain. In the digital world, resolution relates to the number of pixels contained in an image. Every digital image contains a finite number of pixel blocks that are used to describe the tonal information, and the more pixels, the finer its resolving capacity. The pixel dimensions of a digital image are an absolute value: a 3000 × 2400 pixel image could be output as 12" × 15" at 200 pixels per inch and the megabyte file size would be 20.6 MB RGB or 27.5 MB CMYK. A 3500 × 2500 pixel image could reproduce as an A3 or full bleed magazine page printed at the same resolution of 200 pixels per inch and megabyte file size would be about 25 MB RGB (33.4 MB CMYK).
