Calibration - what is it and why use it? In brief, all devices that we use to capture, view and print digital images have different inherent mechanical characteristics. This means that no two different makes of cameras or scanners capture the same image in exactly the same way and with the same values, no two different makes of monitor show an image with identical values and no two different printers will print an image in the same way. When you add in the variables of lighting (both when capturing an image and the ambient lighting when viewing it), monitor settings, paper, temperature and even humidity it is no wonder that some people have 'issues' when it comes to what they eventually get out of their printer compared to what they thought they captured in camera or on scanner!
One process that aims to even out these consistencies is calibration. The sections below outline some of the main steps you can take to ensure you have a better 'system' in which to process and print images:
The first item you can calibrate is what you work with most - your monitor. Paintshop Pro in common with most image programs has a couple of tools to help with calibration.
The primary one is monitor gamma. To view and adjust what you see in Paintshop Pro, use the menu option FILE > PREFERENCES > MONITOR GAMMA. This brings up the dialogue pictured. To 'balance' your monitor adjust the sliders to
get the central colour sections to 'merge' with the background either side. You may want to adjust each colour independently, in which case untick the Link box (arrowed). When you have adjusted it satisfactorily, you might want to make a note of the new Gamma values (circled). Thi is in case you need to repeat the process later. You can also use them as colour adjustment values on images.
Note: This process only ensures correct adjustment in Paintshop Pro - not in other Windows programs.
Tip: One of the primary things users fail to do is examine the current Colour, Contrast and Brightness settings on their monitor prior to trying to adjust anything. Do so before you take any steps, ensuring you set everything to the 'Neutral' or 'Default' settings.
Paintshop Pro (and Windows and other programs) also make use of a software process known as Colour Management. This involves using known digital values for devices you have, including monitors and printers. The values are provided by colour management files (usually with the extension ICM) loaded into Windows.
When you install a printer the ICM file may be loaded into Windows ready for applications to use. Monitor ICM files will usually have to be loaded independently.
To view Paintshop Pro's Colour Management options, use the menu command: FILE > PREFERENCES > COLOR MANAGEMENT. You will see the dialogue box on the left. Note that for my PC the ICM profile for my colour printer has been installed.
Generally you should keep the colour space as sRGB, which is a relatively new standard produced by Adobe.
The most practical step you can take is to use a Reference image - commonly referred to as an 'IT-8 target'. This is an image which has a full range of reproduceable colours and shades and for which you have a supplied print and high quality digital image file. These can be purchased from companies such as Kodak and Agfa. They are also sometimes supplied with some digital image applications and scanners.
They can be used
very simply to compare what you are seeing on your monitor and what is being produced by your printer. All you have to do is load and view/print the image and then adjust your outputs to the printed reference image supplied.
To 'calibrate' your scanner, camera and printer, you can then capture an image of the supplied printed 'scanner target, compare the captured image(s) with the printed example and manually adjust your devices accordingly.
Download a target scanned on my Epson scanner here
Download a target taken with my Olympus camera here
Download a high quality jpeg version of the target here
If you do not have a profile supplied with your monitor or printer, you can create your own profile, using available profiling software. The good news for Adobe Photoshop users is that the software for profiling a monitor is installed into Windows with the program. The link below expands on how to use it:
A guide to creating a monitor profile (web site pictured left)
Getting into this area you have to be a fairly confident PC user and be prepared to note down every step you take and the settings involved - in case you have to return to 'default values' at any point!
The area of calibration is large and daunting and more and more information is made available every day - because more and more new devices come onto the market.
One thing to bear in mind though is that newer devices generally are better made and better supported by Windows, so calibration should not really be necessary.
Some primary information on colour management
Wikipedia's section on colour management - with further links