Services: RGB Media Evaluation Process
How to achieve optimum printer driver settings, as a basis for printer profiling and your colour accurate workflow.If you print direct through the printer driver installed with your printer, rather than via a CMYK RIP, the Media Evaluation Chart should be printed and visually assessed in order to ensure optimum ink and paper settings have been selected in the printer driver.
The objective of optimising the Driver Media Settings is to limit the ink flow characteristics of a printer to the ideal level for the ink and paper combination being used. (This procedure is only required when printing through a Print Driver, not when printing CMYK through a PostScript RIP, as these have their own controls for optimising the ink flow.)
It is important to set the ‘Media Settings’ correctly before profiling in order to produce a good profile and achieve colour accuracy. The following procedure outlines a method for selecting the optimum settings. These ‘Driver Media Settings’ are then used for all subsequent prints in conjunction with the profile that is to be built. This has the added advantage of potentially reducing ink usage.
How to print the RGB Media Evaluation chart
- For printing the Media Evaluation Chart (and for printing the charts for profile building), the Photoshop ‘Print with Preview’ dialogue Colour Handling Option should be set to ‘No Colour Management’ (if printing though other applications, check that no colour management is being applied).
- The Printer Driver settings must also be set correctly. The standard accepted settings are to select the ‘No Colour Management’ option in the printer driver and a ‘Paper Type’ description that matches the paper type being used. It is important that these are correct before printing the charts for measuring your profile. Your selected settings are the basis for all subsequent
- If the paper is not the same brand as the printer being used, the term ‘gloss’ or ‘matt’ as used in the printer driver may not correspond with the same term as used by the paper manufacturer. It is then best to select similar named descriptions as a starting point. (Even if corresponding paper and printer brands are being used, a different brand of ink could result in the paper type descriptions not being ideal).
- Save these Driver settings, as these settings will be used for all future
- Print the chart.
Assessing the printed RGB Evaluation Chart
Identify Scan lines through the solid colour patches (at the end of the cyan, magenta, yellow and black step wedges)This is an indication that the printer ink-heads are blocked. If such a problem is identified, run your printer’s ink-head cleaning procedure and tests to verify they are all printing correctly. A profile based on prints with data missing through a blockage will be invalidated when the blockage clears or worsens.
Check Greyscale for heavy colour cast (white to black step wedge)This is an indication that ‘No Colour Management’ is not the ideal starting point for your particular printer model (an issue with some Epson printers). In such cases we recommend changing the Printer Driver Media Settings from ‘No Colour Management’ to ‘Colour Control’ with the ‘Colour Control’ Gamma set to 2.2 and Mode set to AdobeRGB.
Ink Weight too heavy
The Cyan, Magenta, Yellow and Black step wedges should ideally show an increase in colour intensity at each step and should not flatten off much before the 90%–95% step (do not worry if it is hard to identify the steps in the yellow ramp). Similarly, if the 95%–100% step is evident there is a chance that you are not achieving the full intensity of each colour. The Colour Matrix (below the step wedges) should show pale slight colour shifts on the lightest top row, and the lowest row should be dark, but still show a slight evidence of the different colours.
If these ideals are not met with your current Printer Driver Settings, choose another paper type and reprint the chart. It may not be possible to achieve a result with all the steps clearly
identified up to 95%, but ideally you want to avoid limiting the maximum saturation of the colour at one end, and similarly not having the colours print as solidly at the 60% step.
Ideal settingsWhen you have printer driver settings that achieve optimum results, resave the Preset for future printing of the profile building charts and all subsequent colour managed printing.
- The Verification Control strip is not part of the media evaluation process, but can be used with the photographic images for ongoing verification after
- The photographic images will not necessarily look perfect until you have built a profile and reprinted the chart with the profile
- Printing the colour ramps is used to assess the optimum driver settings when printing with no profile. The result from printing these ramps with a printer profile is not a valid test, and the colours will not look correct.