Colour management hardware and software has matured to a level where it is easy to get really good results. However, things can and do go wrong, even for those of us who’ve been doing this for nearly 20 years. In this blog I’ll outline a few of the problems you may encounter when calibrating and profiling your monitor, their causes and most importantly their solutions.
If your monitor has a colour cast after you have calibrated and profiled it then there are three common causes. It could be that the filters in your colorimeter have deteriorated. A colorimeter such as one of the Spyder or older i1 products have filters in that split the light into roughly red, green and blue. Sometimes these filters can age and end up causing a colour cast when you calibrate. Most commonly it is a magenta cast. So if you do get a cast one thing you can try is borrowing another colorimeter to see if the cast goes, or to try the same colorimeter on another screen. If you get the same cast then it could well be time to upgrade to something like the i1 Display Pro that uses a different kind of filter.
Another common cause of a colour cast is trouble setting the colour temperature of the monitor. If you set a target colour temperature that is lower than you are used to (5000K for example) then the screen may appear to have a yellow cast. Choose 6500K as your target and it will loose this cast. When you set a colour temperature target you are only defining the blue to yellow colour axis and not the green to magenta tint. So sometimes forcing a screen to 6500K, for example, gives it a slightly green or magenta tint. If this happens then try selecting native white point in your calibration software. This will leave the white point of your screen alone and should get rid of the cast.
Whatever colour temperature target you choose make sure you are doing as much of the adjustment as you can in the monitor hardware controls as you calibrate and not letting the software edit the graphics card look up table to get the screen to that white point. This will usually minimise the risk of colour casts. The only exception would be if you are using a cheaper monitor with very poor controls that actually introduce a cast. In which case reset the monitor and either let the adjustment happen in the LUT or select native white point.
The last common cause of a cast is that the colorimeter you are using isn’t appropriate for the type of monitor you have. Older colorimeters such as the Spyder2 series were optimised for monitors with sRGB gamuts and won’t work well on wider gamut models. Newer systems such as the i1 Display Pro have user selectable settings for CCFL, wide Gamut CCFL, White LED and RGB LED backlights amongst other so find out what type of back light and gamut your monitor has, or just experimenting, may get you a better calibration.
Not Matching to Printer
This is too big a topic for this blog, take a look at this post that tackles the issue in detail.
Before & After doesn’t show a change
Some monitor calibration and profiling software shows you a before and after view at the end of the process. Sometimes users are surprised to see almost no difference and wonder why they bothered calibrating in the first place. Actually getting almost no difference in the before and after is a good thing and means you’ve done the calibration really well. The before and after works by changing the look up table in the graphics card, resetting it back to what it was for before and then loading the new LUT again for after. The best calibrations are achieved by adjusting the monitor to the target settings as you go through the calibration process. The better job you do the less the software has to change in the LUT. So if you take your time to adjust the monitor brightness and white point to your targets and your monitor controls are good then the lack of a before and after change just means no adjustments are being made in the graphics card LUT and you have done a great job.
Things look great in Photoshop but over saturated in my web browser
Photoshop, Lightroom, InDesign and many other applications access the monitor profile to know exactly the colour gamut of your monitor and the output to the monitor is adjusted on the fly to make sure you see your data accurately. However, some web browsers, operating system interfaces and simple picture viewers etc don’t use the monitor profile. They just assume your monitor is sRGB. So if you have a monitor with a near Adobe RGB colour gamut un-colour managed content will look too saturated. The best solution for this can be just to live with it because if an app is not colour managed then almost by definition you are not doing anything colour critical in it. If you want a better web browsing experience then use Firefox, as it does use the monitor profile. Check out this post for more detail.
Images looks good in Photoshop but really dark in Internet Explorer
This can be a slightly different problem to the one above. The International Color Consortium regularly meet to update the specifications of the ICC profile file format. The latest version is 4.2 and lots of profiling software defaults to making version 4 profiles. However, some older applications such as Internet Explorer cannot use version 4 profiles and you get a very dark looking image if you try. The solution is to change the setting in your profiling software to version 2 which is far more compatible with older applications. So if you get odd, dark results in some software but not others then change the setting to version to and reprofile your monitor. Conversely I have known some rare and specific cases where the opposite was true, the software needed v4 not version 2.
There are few insurmountable problems when it comes to monitor calibration. If you get poor results, don’t give up just get some advice and have another go.
If I haven’t covered the problem you’ve had then please comment on this blog. I will cover troubleshooting printer profiles in a later post.