Test images and calibration products:
Calibrating your monitor requires you to use a number of test images. As you adjust your settings, certain points on the test image will change, become visible or fade from view. You can buy software and hardware to help you calibrate your monitor, but there are also a number of free tools and test images available on the internet.
http://www.photofriday.com/calibrate.php - A simple test image that helps with adjusting the brightness and contrast of your screen.
http://www.lagom.nl/lcd-test/ - A more complex series of test images, which also help adjust Gamma and sharpness settings.
- Before starting calibration, make sure your computer is set to the highest resolution and colour settings it can display.
- Calibrate in a room that isn’t too bright, and ensure there is no glare from lights or windows on the screen.
- Leave your monitor on for about half an hour before starting calibration.
- If you have any colour management features running through your graphics card, turn them off.
- When possible, make adjustments to the display through your computer and then save the changes as a new colour profile.
- Your monitor and computer user guides will tell you how you can alter your display settings.
Contrast and Brightness:
Contrast controls how brightly your monitor displays colours, or the white level. Brightness controls the darker end of the colour spectrum displays, or the black level.
- If the Contrast is set too high, brighter colours and shades will blend into each other making them all appear the same.
- If Brightness is set too low, darker colours and shades lose detail and vanish into each other.
- Setting your Brightness too high will make blacks start to appear grey and washed out.
- Lowering your Contrast too far will stop whites appearing vibrant and make them start to appear grey.
The software or test pattern you are using will give you exact instructions on how to make the adjustments. Normally this will involve changing the settings until certain dark and light shades become visible in the pattern.
The monitor’s Gamma level is, roughly described, how much light the screen displays. Changing this level has an effect on all the other display settings, and it may need to be adjusted in order to get the best results from other tests.
- The optimal Gamma rating for most computer monitors is around 2.2
Your calibration software will have instructions on changing the levels to set the Gamma to this rating. The method will be very similar to how you set Contrast and Brightness.
While many other options can also be altered by the computer, Sharpness is normally only set by the monitor. Rather than actually adding more detail, this setting adjusts how fine detail is displayed. When set too high, it can make objects look like they have a slightly fringed outline or cause a strobing or flashing effect.
Each individual pixel on your screen displays a blend of several different colours - normally red, green and blue. By changing the levels of each colour, your computer is able to reproduce every shade and colour imaginable, including black and white. Most computers and monitors will allow you to alter settings for each individual colour channel.
This can be the hardest part of your display to calibrate. Certain software and hardware will do this automatically, taking readings from your screen and adjusting for optimal settings.
If you are performing this step manually it is best to use a Monitor Calibration Test Image. There are a number of these available for download on the internet. These images contain colour bars and a variety of pictures designed to cover a comprehensive range of tones and hues. If you don’t want to use one of these, you can also use a good quality photo of your own as long as it contains a wide range of colours:
- Print your test image.
- Compare the printed version to the image on the screen.
- Adjust the levels for each colour either on the computer or monitor.
- Keep making small changes to each colour channel until the image on the screen matches the printed copy as closely as possible.
- Save the changed settings.
- Reprint the test image and compare it again. The results should be much closer. Repeat the above steps until the monitor and printout images are as close as you can get them.
The whole process can take a little time the first time you do it, but once calibration is complete you’ll find you only need to make smaller adjustments in future and the whole process will be easier. You may also need to repeat the process if you use more than one printer. If this is the case, ensure you save the different settings as their own individual colour profiles.
While it’s easier to complete this process by purchasing a specialist calibration tool, a little effort can produce great results. Now you can see exactly what you print, it makes setting up your home photo lab that little bit easier.