Monitor Calibration Made Easy
The first step to achieving colour consistency involves calibrating your computer monitor and creating an ICC profile that can be used by the editing software as a working RGB colour space. The objective is to make the image you see on the monitor look as close as possible to the print you make from it.
Start by warming up the monitor for at least 30 minutes and ensure your room lighting will remain constant throughout the calibration process. It’s best to work in lighting that is slightly dimmer than normal room lighting because bright ambient light can cause the colours you see on your monitor to look washed-out and lacking in contrast – so what you see may not be what you get in a print. Note: To ensure consistent results, maintain the same type and level of lighting when you calibrate your monitor and edit and print your photos.
For users of basic image editors:
Step 1: Refer to your monitor’s instruction manual to find out how to adjust its brightness, contrast and gamma controls. Set your monitor’s brightness and contrast controls at their exact mid points (half way between the brightest and darkest settings). Then, with the gamma control, set the white point to 6500K.
If you are using Windows XP, clicking on Control Panel>Display> Settings then click Advanced and select Color Management from the menu bar. This will reveal all the profiles that have been associated with your monitor. If this is the first time you have profiled the monitor, the manufacturer’s pre-set profile is the only one that will appear. If you have profiled the monitor before, the current profile is highlighted, as shown in the illustration below.
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Colour reference cards, such as the one shown above, provide a useful reference for monitor calibration.
Step 2: Open a reference image in the software you are using. Although you can use any photograph that has a suitable range of hues and tones, the best results will be obtained with properly calibrated reference cards. Options include the GretagMacbeth Colour chart and a much less expensive alternative set of cards from Perfect-Pixs, which includes both a greyscale ‘Zone’ card and a ‘Patches’ card covering the primary RGB and CYM colours. (Distributed in Australia by Vanbar Imaging – www.vanbar.com.au.)
You can use the Perfect-Pixs Zone card to check your monitor’s brightness. If the monitor is correctly adjusted you should see 11 distinct zones, ranging from deep black to pure white. If you see any colour casts, your monitor’s colour balance is off.
If you are using the Perfect-Pixs cards, open the PatchesCard file from the supplied CD in your editing software and compare it with the printed card that is included in the bundle. The colours on the card should appear slightly darker and duller than the monitor display but the actual hues and tones should match as closely as possible.
Step 3: Follow the instructions laid out in your printer’s manual for printing a colour photo at the best quality and make a print of the reference image file. Where a choice of colour modes is available, select RGB for this step.
Step 4: Allow the print to dry for at least 10 minutes then compare it with the image on your monitor. Then use the brightness, contrast and colour controls in the software to make the image on the monitor look as much like the print as possible.
Note: This is a very rough method of monitor calibration so don’t be surprised if you don’t get perfect results first time. You will probably need to repeat the exercise several times to obtain a print you are happy with.
For Photoshop users:
Adobe Photoshop and Photoshop Elements have a built-in Adobe Gamma utility that makes monitor calibration easy. It also lets you adjust the Gamma, White Point, Black Point, Mid Tone Point, and the colour balance of each of those areas. The Photoshop installer installs Adobe Gamma control panel (Adobe Gamma.cpl) into the Program Files/Common Files/Adobe/Calibration (Windows XP and 2000), and at the same time installs the Adobe Gamma loader application (Adobe Gamma Loader.exe) into the Program Files/Common Files/Adobe/Calibration folder. A shortcut to the Adobe Gamma Loader application is also placed in the Documents and Settings/All Users/Start Menu/Programs/Setup (Windows XP and 2000).
Step 1: If you’re a Windows user, select Start>Settings>Control Panel and double-click on Adobe Gamma.
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Step 2: Select Step By Step Wizard, then click Next. The Wizard/Assistant will take you through the process of monitor calibration, which involves setting monitor brightness. In the Description panel, type a new name for the profile. Most photographers use the monitor model name and date so they can easily find out when the monitor was last calibrated.
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Step 3: Click Next and follow the on-screen instructions. Adjust the monitor’s brightness level until the inner square on the panel is just visible. Click Next.
Step 4: Before you save the settings, you should view the changes you have made by clicking on the Before and After buttons. To save your settings, click on Finish. Save the profile in the Windows > System > Color file (extension .icm) or Mac OS system Folder > ColorSync Profiles. Use the name you typed into the Description panel in Step 2.
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Adobe Gamma will save the new profile in the Windows/System32/Spool/Drivers/Color folder for Windows 2000 and XP. Because monitor colours can drift, you should repeat this process at least once each month to ensure your monitor remains properly calibrated.
Colorimeter Calibration
Photographers who do a lot of colour printing, particularly at large output sizes, will find it easier (and usually more cost-effective) to invest in a colorimeter. This is a device that measures the colours displayed on the monitor screen and uses software to create ICC profiles. If you plan to use a colorimeter, you should prevent Adobe Gamma from applying its settings at the system level when Windows starts. This avoids conflicts that might cause inaccurate displays.
To prevent Adobe Gamma from loading its settings at startup, remove Adobe Gamma Loader by double-clicking on My Computer and navigating to Documents and Settings>All Users>Start Menu>Programs>Startup. Select Adobe Gamma Loader, and drag it onto the desktop. This step ensures that Adobe Gamma will still be available in the Control Panel, but its settings aren’t loaded when Windows starts.
The cheapest and simplest colorimeter is the Pantone Huey, which looks like a marker pen and is wizard driven and straightforward to use. We’ll use this product to illustrate the basic steps involved in calibrating a monitor with a colorimeter. Other, more sophisticated, products include the EyeOne Display 2 and the ColorVision Spyder.
Step 1: Start by loading the software, cleaning the monitor screen and making sure the monitor is evenly-lit with no reflections off its surface. Plug the colorimeter into the computer’s USB port. The Huey can measure the ambient lighting in the room and take it into account when producing the monitor profile. Directions are provided for this step, which takes less than a minute.
Step 2: When you open the calibration program you are then prompted to attach the colorimeter to your screen. (With LCD monitors it’s best to tilt the screen backwards until the colorimeter stays in place.
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Step 3: Click Next to start the calibration process. The screen turns black and a white oval appears beneath the colorimeter, along with a progress screen on the left side. Green dots light up on this screen as the calibration process runs through the different colour patches. You must not use the computer for anything else while this is happening.
Step 4: In less than five minutes an oval dialog box reappears with the ‘Calibration Successful!’ message and you are instructed to return the sensor to its cradle. Touching the Next button displays a GretagMacbeth ColorChecker pattern plus a picture of a model. Two buttons below this illustration let you toggle between the corrected and uncorrected modes.
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Step 5: The next screen lets you select the calibration setting that best matches your main usage of the monitor. Selecting ‘Web Browsing & Photo Editing’ is the best option for most photographic tasks.
Step 6: The final screen allows you to set the software to update your calibration when the room lighting changes. This requires you to keep the device in its cradle and connected to the computer, which you may not want to do if you don’t have a spare USB port. The software can also provide reminders for recalibration. Windows users can locate the profile by right-clicking on the desktop then selecting Properties>Settings>Advanced>Colour Management. The software will use the monitor’s model number as part of the identifier.
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