Spectrometers measure light intensity and its composition, so they are obviously the instrument of choice for measuring printed colour data. They analyse wavelengths, recording how much of a particular wavelength the target returns. The basis of CIE metrics, and so colour management, is the spectrum of colours the spectrophotometer captures from a given sample.

A spectrophotometer is about as clever as it gets when it comes to measuring devices used in the graphic arts. Commercial printers who pride themselves on their colour management expertise shouldn't be seen dead without this vital accessory.

A manual spectrophotometer, such as the popular EyeOne, can be more flexible for the business than its onboard equivalent

Rather than being a portable freestanding tool, an onboard spectrophotometer is built into a printer. This has been made possible due to advances in technology to get the size of the instruments down, and to falling costs as uptake spreads. Onboard spectrophotometers are used for automated quality control, feeding data back to the device's colour management system. They are handy for checking the print performance and they can also be used for keeping in touch with remote devices. How useful they are depends on the instrument and the application.

For much sign and display work a spectrophotometer may be overkill, since it captures the full spectrum of colour in a given target. Such detailed colour information may not be needed, for instance to produce low-resolution prints with long viewing distances. However even at low resolution you still want the colours to be correct, particularly if you are printing brand colours. For absolutely spot-on colour accuracy, machines must be regularly calibrated and that requires a spectrophotometer.

For machines that double as poster and even proofing engines, an onboard spectrophotometer might be useful, but spectrophotometry is arguably more important for photographic work than it is for signs and displays. That said, improved output quality for short viewing distance work could give a sign and display producer the edge, particularly for applications such as POP and indoor signage. And the trend in commercial printing is to include an onboard spectrophotometer on all new presses. The idea is to provide the tools for full process automation and control and, as quality improvement expectations have a habit of spreading, the wide-format sector should also be interested in onboard spectrophotometry.

But a spectrophotometer must be used in the context of a wider colour management strategy. These devices aren't cheap and they mean an extra cost to a new engine. Unless there is a complete colour management strategy for the business, an onboard spectrophotometer won't really worth the premium.