As with all devices which we use in the imaging process for managing colour, the others being camera and computer monitor, printers do not natively give a rendition which is 100% accurate and it is necessary to apply a correction, known as a printer profile, when printing. The corrections required will vary according both to the inkset which is in use and the type of paper, so it is necessary to use a separate profile for each combination of printer and paper which you use. The good news is that unlike monitor calibration, printer profiling only has to be done once since and there are a number of different ways of obtaining them.
- If using the printer manufacturer's own paper, the correct profiles are usually incorporated into the printer driver.
- Paper manufacturers invariably provide generic profiles for the most common printers used in the production of photographs. Given that there is little variation between individual printers, these are often sufficient for most purposes.
- Bespoke profiles which exactly match printer and paper can be purchased from third parties. Fotospeed and Permajet provide this service free of charge for their own papers. This is the most cost effective method if only a few profiles are required.
- DIY profiles can be made. Datacolor and X-Rite both offer equipment for doing this, the latter having the ColorMunki Photo for home use and various Eye One devices for professionals and the well heeled. The cost can be recouped if a lot of profiles are required and the systems also provide options to tailor the profiles to suit individual requirements.
Whatever system is used, printer profiles are all created in the same way. A series of colour patches are printed and then, after being allowed to dry fully, are measured by the profiling software to analyse the deviation so that the profile can be created. Normally only a few hundred patches are required to achieve accurate results, but some people will use considerably more on occasion. Low cost measuring devices have to scan the patches manually, but high end devices can do it automatically.
Installing printer profiles is a breeze for Windows. Right clicking on the profile's icon in Windows Explorer brings up an "Install Profile" option, which automatically places the profile in the correct folder when selected. The situation for Apple Macs appears to be more complicated, but I did find this information on the internet. Fortunately, it only has to be done the once.
http://www.drycreekphoto.com/Learn/profile_install.htm
The application from which prints are being made has to support the use of printer profiles. In a backward step, Adobe has dropped this function from the more recent versions of Photoshop Elements, which means that profiles can only be invoked when using the printer manufacturer's paper. It is still present in Photoshop CS and Lightroom, with the latter only supporting printing via profiles in version 4 although it is available in earlier incarnations. There are many other programmes which use printer profiles, but I have no personal experience of them.
In Photoshop CS, there is a drop down option in the print dialogue with the options "Printer Manages Colours" and "Photoshop Manages Colours". If selecting the former (or Photoshop Elements), the paper has to be selected in the printer driver's dialogue. For the latter (or Lightroom 4), the correct printer profile has to be selected from another drop down box which shows all the profiles installed on the computer. If the incorrect profile is selected, it is very unlikely that the colours will be correct and a reprint will be required.
If the preview option is selected in the printer driver, the colours will not look right because they have been adjusted by the printer profile. In essence, the preview is only good for checking that the print will be made at the correct size and is properly positioned on the paper. It does give a very good indication of how much variance there is between the colours the printer is expecting to print and what actually gets printed.
There is one other use for printer profiles in Photoshop CS and Lightroom since version 4 and that is soft proofing. This provides a preview on the computer's monitor of how an image will look when it is printed and is useful for making corrections before the expense of committing it to paper.
To conclude, there is little to be gained from using printer profiles in isolation and the monitor also has to be calibrated in order to get prints which match what is seen on the screen. There are some limitations to this, for a variety of reasons.
- Most people use low end monitors which are limited to the sRGB colour space and cannot show the full range of colours which will be in the final print. Monitors which show most of the colours available in the wider Adobe RGB colour space are available, but are significantly more expensive. That said, they have also dropped massively in price since their introduction a few years ago.
- Images on screen are lit from behind, whereas prints are viewed by reflected light. This difference in illumination will effect how the colours are seen.
- Computer monitors create colours by mixing dots which comprise of Red, Green and Blue (RGB). Inkjet colours are created from Cyan (blue/green), Magenta (purplish red), Yellow and blacK (CMYK - K is used for black since B represents blue). Some printers also include red and green inks, but the range of colours in a print will still be different.
- The range of contrast in a print is lower than on a computer monitor.
Despite these differences, it is still possible to obtain prints which very closely represent the computer display provided the correct colour management steps have been followed throughout the process.