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GO DIRECTLY TO PRINTER PROFILING
SCANNER and PRINTER PROFILING WITH THE EYE-ONE PRO DEVICE The Eye-One Pro is a multifunctional spectral measurement device which contains a holographic diffraction grating with a diode array detector, suitable for measuring spectral data from 380-780nm in 10nm steps. It is the first choice of measurement device for printer and scanner profiling, the two key color management related tasks to ensure correct, consistent and predictable color throughout the entire process from acquisition to printing. The Eye-One Pro device is the only device you need for all tasks regarding color management for photographers. You can start with its basic function to calibrate monitors and add the functionality of profiling RGB printers by choosing the Eye-One Photo option. The specification for his package can be found here: Eye-One Photo If you like to get a package which not only can provide monitor calibration and RGB printer profiling but additionally also scanner and CMYK printer profiling, then you need to choose the "Publish" option of the Eye-One system. Its specification can be found here: Eye-One Publish For most photographers not that important, but for many business related applications of interest is that package, which allows to calibrate monitors and beamers (digital projectors), this package is the Eye-One Beamer and its specifications can be found here: Eye-One Beamer If you prefer to pick and choose yourself and want other packages or additional options, then you should look what is available on that website here: Eye-One Bundles I would like to suggest that you walk through the entire process of profiling your color chain by browsing through these tutorials one by one - you have done the monitor calibration by now, next is scanner and then comes printer profiling. If you do not have a scanner, then go directly to the printer profiling through this link: GO DIRECTLY TO PRINTER PROFILING
SCANNER PROFILING The connection of the Eye-One Pro is similar to the Eye-One Display 2, it is an USB connection and as soon as you have connected the device to the computer, the installed program, Eye-One Match 3, recognizes it and displays the device as active throughout all program tasks. First I want to take you through the profiling of a scanner - I use my own Epson 4870 Photo scanner as the scanner of choice. This scanner is affordable and produces very good scans for my main areas of interest, which is scanning of 120/22- and 4x5 inch film ( positive and negative ) for printing and publishing. There is one topic, which needs to be mentioned - many SW scanner packages, which are included in the scanner package, do not include the feature of color management. You can therefore either use the profiles in Photoshop ( color management settings ) or buy a scan SW, which allows to apply scanner profiles - like Silverfast Ai (the full SW, not the SE version ) or VUESCAN ( which I have reviewed here: VUESCAN Review ) So lets assume, that you either use Photoshop to apply the scanner profile or one of the mentioned scan SW packages, now lets start the profiling process. Here is the opening screen, on which you selected the task - scanner profiling - by clicking on the scanner logo. You are offered to either do it as Transmission scan or Reflection scan. REFLECTION SCAN PROFILING To start with, I have selected Reflection scan. Pressing the go-right/next button takes me to the next screen.
Now you have to decide and start thinking - the task is to profile a scanner and we have not done this before - so you should read the "Help" information on the right side of the panel - it tells you clearly that you first have to measure the provided reference reflection chart with the Eye-One Pro device, store the measured values, then scan the very same chart with your scanner and then let the program calculate the profile. Well, lets start now - First of all you need to calibrate the Eye-One Pro measurement device - the next screen shows you what to do - you place the device on the included calibration target and press the button on the device which is on its left side.
Now the calibration starts and the progress is shown on the next screen -
As soon as it finished, you get the completion message on screen and can go to the next step. Take the included reference chart for reflection scanning out of the protection envelope and put it flat on a suitable surface. Take the plastic ruler with the long opening and place it on top of the chart, starting at row 1. It is not critical to put it dead in the center so that the white areas on both sides are identical, just leave enough space on both ends so that the measurement device can see that the row has ended and the white end has come. As you can see, you can select between two different modes of operation - Strip Mode and Patch Mode. Yes, you could measure every single color patch individually, if you want, but to make it easy, choose Strip mode - the program now expects you to glide over these patches, row by row from row #1 to row#16. It does NOT matter on which end of the patches you start - let of right ( here in the screenshot upper end or lower end ), as long as you keep moving from row #1 to row#2, #3 etc. If you skip a row, you get an error message, if you move to fast, you get an error message, if you made a mistake, you get an error message - so you cannot do anything wrong ( believe me, I tried it out )
Again to be clear - you put the transparent plastic ruler in the shown way over the reference chart and place the measurement device in such a way on the plastic ruler that the front of the device is sitting well in the opening of the ruler - that's where the measurement head itself will read the colors of the chart. Now press the side button on the device, wait until you hear a short beep and then move with a reasonable speed over the chart, always inside the ruler's opening. It is easier than it sounds - just keep sliding and do it at a reasonable speed - it is not critical to be exactly at the same speed or how fast you do it within limits, just move it over the open area inside the ruler's window. BUT KEEP THE BUTTON PRESSED during that movement, otherwise you get an error message - Pressing the button activates the head's measurement system and when you reach the end on the other side, just let the button go - you hear another short sound and see that the measurement window as shown in the next screenshot was accepted. Here is that screenshot after sliding over the first few rows of color patches:
If you made a mistake - moved too fast or scanned the wrong row - you get an error message like this one:
Once you are finished with scanning all the rows, you see that the previously (partially) grayish chart is completely colored and this is the end of your measuring activity - here you see how it will look:
Now you can proceed to the next step - the reference chart is measured, the very same chart has to be scanned with the scanner you want to profile to get the color input as the scanner sees it. Be sure to turn off all color management options in the scanner SW for this scan, scan at or about 300dpi, 100% enlargement ( original size ) and store the output as TIF file ( preferably raw TIF RGB ). All scanners should be able to store the file as TIF file, it will be about 18MB in size without any compression. If have done this with the EPSON SW which was delivered with the scanner and of course I have disabled all color management in the SW setup options. Here is how that raw scan looks like - you see, the colors are not really good compared to the measured reference chart:
The next step is obvious - you have to load this raw scanned reference chart into your profiling program and let the SW calculate the profile for the scanner - don't forget what you have got already: You have got the reference chart measured and therefore the program knows the colorimetric data of all the patches on the chart. The scanned patches will most definitely have a different color compared to the original patches, so the program will now compare the patches, one by one and calculate the differences between original and scan and this is then the foundation for the scanner profile - the profile is an color related information how a certain color is reproduced or changed in that scanner during the scanning process to make sure that if that color is scanned, it will be converted back to the original color. As you can imagine, you could take thousands of different colors, color saturations, shades, intensities, brightness values etc to create such conversion curves, but the chart we use, is fine for most work you encounter. If you want to make the profile even more precise, well, you can do so by picking another reference chart, one which contains even more patches. There are charts available for almost any reasonable degree of precision wanted. Lets move on to the next screenshot as you have loaded the scanned reference TIF file by now - here is the next screen:
To enable the program to match the right patches
properly, you need to crop the loaded chart by dragging the corners of the
dotted area to the outer ends of the color chart - a magnifying glass helps you
to position the corners properly. It is necessary to position them pretty well,
so take some effort and do it nicely - see next screenshot: You see inside the magnifying glass that I positioned the lower left corner as good as possible - it helps to avoid miscalculations. But do not make an art out of this task, it is not necessary to position the corner mask exactly to one pixel precision...
Now the next screen lets you see both charts - an image of the original one, the reference chart and an image of your scanned chart and they should look similar. If not - check the orientation of your scanned file, it might be wrong, so correct it until the charts look similar.
You are almost done by now, if you see what I have printed here, then you are fine - press the "next" button and it takes you to the screen which tells you that the profile is calculated. Then comes the screen which asks you to store the profile and if you like, give it a special name, so that you can easily recognize it among the many other stored profiles on your computer.
As you can see, I called it 4870Flatbed_Scanner + the date on which it was done - you know, Windows XP stores the profiles in the folder Windows/system32/spool/drivers/color - and you will find there a lot of profiles when you work with Photoshop and/or similar programs. You store the profile and you are done - when you open your photographic manipulation and enhancement program, like Photoshop, then open the color management options and select this profile as your scanner profile and your scans with be scanned and properly imported into your photographic enhancement and manipulation program. The next task, I am going to walk you through, is profiling of a transmission target ( IT-8) for slides. TRANSMISSION SCAN PROFILING Profiling a scanner for a transmission target ( slide film ) is similar and easy as well with the Eye-One Pro device. The steps are the following after you have selected transmission scan on the first page of the scanner profiling menu:
You need a transmission target with the IT8 patch pattern for this purpose. There are many sources for these targets, among them Kodak, Fuji and several independent providers of good targets. Why do you need such a target - well, remember for reflective scan target profiling, you need to scan the included target and then compare the scan with the data of the original - here it is the same approach but as there are many different color slide film brands on the market and all of them render the color patches slightly different, you need first to decide, which film you are going to use for this task. It should be the film , which you are using for your photographic work, so it is not wise to profile a scanner with a Kodak Ektachrome film and expect that your slides, taken on Fuji Provia turn out perfect in color. I used for this task the IT8.7 ANSI Standard 4x5inch target ( Q60 ) from Kodak on Kodak Ektachrome Professional. The color targets set comes in three different target versions - 35mm, 4x5inch and a 5x7inch print on Kodak Professional Paper. For those how are interested in additional information ( it is really worth reading!) about IT8 targets and color spaces - see my page here: IT8 Target Information
Back to the screen - what to do next? As you see, the program asks you to load a reference chart - using the Kodak Q60 target, you get together with that target a CD which contains the data of the three targets, so you need to locate the appropriate data file and load it. For the Kodak Q60 targets, the data do not come as text file as the program expects them to come, but as HTML file.
You will be able to see the files on the CD once you have changed the file selector in the pop-up menu to display all files, not only text files ( to *.* instead of *.txt ). The correct file is the one which contains the string 405 which indicates that this is the 4x5inch data file. Load it and then go to the next step.
Now the program tells you to load the scanned file - this means that you now have to interrupt your work on this program and scan the 4x5inch file with the transmitted light device of your scanner. Do not forget to turn off all color management options in your scanning program and scan with about 300dpi and 100% size and save it as TIF file.
I have used the EPSON scan routine for this tasks and as you can see, in the configuration settings, I have selected No Color Correction for this scan as well as on the main menu 24bit Color and 300dpi. If you use Silverfast SE, you can get of course the same results, just again - 100% scale, 300dpi and do not click on the automatic color adjustment buttons - just press scan ( after framing the target properly )and save as TIF file.
The file which has been stored as TIF file is now selected and loaded into the Eye-One Match 3 program to be compared with the already loaded data file of the same target. To do this, you need again, similar to the reflective scan profiling, crop the test chart to enable the program to find the right patches for its calculation of the profile.
As you can see here, the test chart for transmission scan does not look like the one for reflective scan, so use this screenshot as guide how to align the crop marks. They need to be aligned according to this screenshot here:
This is easy as well and can be done within less than one minute - the magnifying glass helps you again to properly align the borders according to the requirements. Now you are almost done already. Press the next/right button and this takes you to the step where the program shows both charts - the one on the left contains the data from the Q60 data file and the one on the right is the one you just scanned. If they look similar, you have oriented the scans properly and the calculation of the profile can start by pressing the next/right button on the screen
The profile is calculated and you are asked again to store the profile - assign a name to it which allows you to pick it out among the many profiles you will find there in that folder ( Windows XP stores them in Windows/system32/spool/driver/color ). You can see on the following screen that I have renamed the profile so that I can identify it easily:
No you are done - the transmission scan profile is done and stored. Your scanner is now profiled for both tasks - reflective and transmission targets. Do not forget to use these profiles in your photographic enhancement and/or scanning program. If you use a scanning program like VUESCAN, you can directly enter the location of the profiles in the program preferences. 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 That was easy as well, right? Well there is one more task, which needs to be done and this is to profile the printer. You find this presentation of how to do it here: PROFILING THE PRINTER WITH EYE-ONE PRO
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