Colour Correction in Monitors & Print

“Image fidelity refers to the ability of a process to render an image accurately, without any visible distortion or information loss.” Silverstein & Farrel (2004)

The process of copying a piece of artwork to a computer screen, in its weakest form, would be either translating the image (from email, storage, internet, etc.) from a graphics format into another to allow us to read it or via acquiring the image by scanning it. Both of these processes rely on hardware and software which can cause bottlenecks and hence distortion or information loss. In addition, the way we process colour with our eyes, even ignoring our individual abilities in this respect, can present further issues.

The key to minimising problems in our computer environment is to ensure that our hardware and software is capable of accepting and presenting whatever we are processing at the same resolution and colour profile, something normally that only commercial level equipment can produce well with the latest LCD screens have made great advances recently according to NEC (2011). The best we can hope for is that the image we are processing is not too complex for our graphics card, our processor, our monitor or our software. The higher the specifications on these hardware devices, the better results we can expect. We also need to take care when scanning as even if we have a scanner capable of producing the same resolution as our screen can present, slight errors in placing images on the glass for scanning can have a large impact.

We had a relevant situation with a client in the production of the printed Yellow Pages in the UK. The problem we faced was one where advertising customers saw (and approved) full colour proofs of their adverts (from a commercial Xerox printer) yet when the final directory was published by a third party, complaints and refusals to pay for their adverts ensued as their approved proof was not exactly the same as the printed product, often with reduced or different colour in key items such as logos and branding. This difference was due to a lack of good colour reproduction between the production devices. We therefore set about to standardise, to ICC profiles, the colour reproduction throughout all processes on the printers but also on any computer screen used in the process (hardware was already standardised to identical Mac G4s). The printers were relatively simple as we could program the required colour profile, however CRT computer screens had to be replaced with ones that could be mapped to the same colour profiles and these had to be regularly calibrated to ensure that what the customer approved was what the designer saw which was the printer printed in the final product.

References

NEC (2011) When Colour is Critical [Online]. Available at http://www.nec.com.au/…/Brochure_Colour_Critical.pdf-1e2ae0ce-8390-40e9-a77c-86848f82dbfd-0.pdf (Accessed 20 Feb 2011).

Silverstein, D. & Farrel, J. (2004) THE RELATIONSHIP BETWEEN IMAGE FIDELITY AND IMAGE QUALITY [Online]. Available at http://scien.stanford.edu/jfsite/Papers/ImageQuality/FidQual.pdf (Accessed 20 Feb 2011).