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PROFILING THE PRINTER WITH EYE-ONE PRO
There is one more task which needs to be done to close the chain from acquiring the image to the final step, printing - this is to profile the printer. Up to now, we have ensured that color is predictable , consistent and like "WYSIWYG" because we have calibrated the monitor and profiled the scanner. If you are using a digital camera, then you can profile your camera in the same way as you did it with the scanner - you just need to take a picture of an IT-8 target and then process it accordingly. What needs now to be done to profile a printer - again, I will demonstrate the steps to be taken by using the same multifunctional device, the Eye-One Pro. Start the program, then select as task the printer icon and what you see is this:
The following screen asks you to select the printer you want to have profiled - there are two basically different kind of printers which can be selected - RGB printers and CMYK printers. Usually a home base printer will be an RGB printer, which means, it prints with the colors Red, Green and Blue - sometimes with three, often now with more than three colors, but all of them are shades of Red, Green and Blue. I have chosen RGB and therefore I get a printer icon, which happens to be exactly the printer I used for this review, an inexpensive Epson Stylus Photo 820, and you can see the three colors as puddles in front of the printer to make sure that you have selected an RGB printer. Another selection you have to make is the kind of color target you want to print for calculating the printer profile - for RGB, there are two different targets available, this one, which you can see and a second one, which is much more elaborate and creates an even more refined profile. For any normal requirements, I suggest you to use this simpler target, as it requires only one sheet to be printed and measured, whereas the second target requires two sheets to be printed and measured.
This here is the more elaborate target which creates the best of the best profiles but believe me, you most likely won't need this precision for your printouts unless you use a very sophisticated RGB printer and want to be sure that even the most finest and most refined shades are absolutely identical - provided your monitor is of comparable quality and performance!
OK, lets go back to the simpler, one-page reference chart and print it first. Make sure, that you have deselected all color correction options which are offered in the printing preferences dialog - see my next screenshot - no color adjustment is mandatory, not optional.
Once you have printed out this chart on the paper of your choice - don't forget, you should make a profile for every different paper you are going to use because the colors are reproduced differently on different papers - let this chart dry a bit. Half an hour or an hour is not a bad advise, even if the paper is instantly dry. There is usually a small color change between a freshly printed and a dry print. As we have done before, we have to calibrate the Eye-One device again, and this is as easy as always. Just press the button on the side of the device and after a few seconds, it tells you on the screen, that the calibration was successful.
The next step is to measure the printout your made on that printer, which you want to profile. The screen shows you again, as we have done it during the scanner profiling routine, what you have to do - take the transparent ruler which guides the device over the color patches, and measure row after row.
Again, I would strongly recommend to use the Strip Mode as it is faster and easier than then Patch Mode. After a few minutes, you are through with all 16 rows and the reference chart has been measured completely.
The next step is to save what you have measured to let the program compare the saved file data with the ones you have measured just now - the file data are the ones, which had been used to create this reference chart for printing, so they are stored in the program.
You save the data, it is not a must, but if you like to have them handy for comparison at a later time, do save them, it does not hurt. Press the next/right button and the program calculates the printer profile.
The profile is built within a minute or so and then you can store it after having given it a name, which you can recognize among the many stored ICC profiles in the Windows folder.
You are done, the printer profile is saved and now you can use it for your printer software or photographic editing program. This whole process was easy, fast and produces the profile which is needed to close to open loop between taking the picture, scanning it and printing the final color picture with colors which are correct, predictable, repeatable, smooth and consistent. One more topic to cover - I have been asked before about it and would like to answer that question here: When should one use the Eye-One Pro version with built-in UV cut-off filter and when would it be not necessary? The answer is that as long as you use profiling SW or other color management SW from Gretag Macbeth, then you do not need the UV cut-off filter in front of the sensor but if you use 3rd party SW or other SW like rips with the sensor, then you should use the version with the built-in UV cut-off filter. The reason is, that many or most inkjet printing papers are using chemicals (whiteners) which transform the incoming UV into blue and such create the impression of a whiter white. A spectral sensor however does read that as an excess of blue and compensates it with more yellow in the profile which results maybe in a slightly yellowish tint in the final output print. Gretag's software however recognizes that and compensates for that part and the resulting profile will therefore provide accurate colors in the output print. One final comment regarding some scanning programs ( like VUESCAN ) which offer built-in algorithms for scanner and printer profiling: These options are easy to use and come free with the program but all those which are using a scanner for profiling, are delivering results of limited accuracy, precision and repeatability. Those flatbed scanners like the Epson 3200 or the Epson 4870 are all using their built-in three-color detector (RGB) for the profiling task. And with all three-color devices, the color rendition for more complex colors and levels of brightness and/or saturation is not very accurate. The Gretag Macbeth EyeOne Pro device uses a spectrophotometer, which covers the entire visible range of the spectrum - therefore the obtained measurement results are far more precise, far more reliable, consistent and predictable. In addition, if you keep in mind that the EyeOne Pro device based programs measure the reference chart with the spectrophotometer before applying it, this additional step alone adds another level of precision and accuracy to the whole profiling process. This needs to be taken into account when it comes to a comparison of various apparently similar methods
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