Copyright © 2010 Kulvinder Singh Matharu. All Rights Reserved
If some of the images on my website seem a bit dark that's because I seem to have a preference for dark images! However, to ensure that the images are being shown correctly, your monitor should be calibrated and set to a luminance level of 90 cd/m2 (ie 90 candelas per square metre). The ideal way would be to use an hardware-based calibration device. In lieu of this, a "quick fix" process for getting your monitor brightness/contrast to an approximately correct level is to make use of the gradient chart shown on this page.
FOR CRT MONITORS:
Set the monitor "Contrast" level to the maximum value. If image distortion occurs or the screen seems too bright then lower "Contrast" until the distortion is reduced. Note that CRT monitors can exhibit severe geometric distortion at high "Contrast" levels.
FOR LCD/TFT MONITORS:
LCD/TFT monitors do not suffer from the same "Contrast"-related geometric distortions that CRTs do, so it is very easy to set the "Contrast" level too high on LCD/TFT monitors...instead, as a starting point, try going for a "Contrast" level that is 30% or 40% of the maximum that your monitor can achieve. This is the hardest and most subjective setting to achieve without a hardware-based calibration device. For better charts/software tools please visit Norman Koren's site and The Lagom LCD monitor test pages.
Starting from a "Brightness" level of 0% (ie zero) on your monitor controls, increase the monitor "Brightness" level so that you can see all 21 distinct shades in the test bar shown below. The goal is to keep the black bar as black as possible (so that blacks appear black on photos).
It helps if the room lighting is not too bright, and that the monitor has been in use for at least 30 minutes. Not all monitors will be able to pass this test. In particular, unless ambient lighting is very low it may be difficult to differentiate between the two darkest levels. However, with rapid advances in technology, an increasingly growing number of monitors are able to pass this subjective test with comparative ease.
I have found that a number of LCD/TFT monitors exhibit quite noticeable colour artefacts such that each greyscale bar appears to have a different tint from other greyscale bars resulting in some looking red, some green, etc. You'll have to decide for yourself if you want to (or even can) rectify this.
If my images still appear dark, then sorry, that's the way that I've done them. I did say that I prefer dark images!
Many new flat-panel monitors (eg LCD/TFT monitors) being sold today have white luminance levels factory-set at 200+ cd/m2 which is VERY bright (these high white luminance values certainly make the images stand out in a showroom). Accordingly, those using older CRT monitors may see darker images than those using newer LCD monitors. When I first got an LCD monitor after retiring my CRT, it took me a long time to dial down to 90 cd/m2 instead of using the factory default of 190 cd/m2...at first 90 cd/m2 appeared too dim. You may experience the same! Why have I used 90 cd/m2 white luminance level? Simple...so that the images on the screen match those printed out.
Remember, this page is purely a "quick-fix". There are other monitor calibration charts and software tools that you can use that are more accurate than what I've presented here. Please visit Norman Koren's site and The Lagom LCD monitor test pages. Highly recommended.
If it helps anyone (and each monitor is different and subject to ageing), I use a Dell UltraSharp 3008WFP 30-inch monitor.
Using the monitor controls I have set:
1. Contrast = 50%
2. Brightness = 31%
4. Red = 100%
5. Green = 91%
6. Blue = 94%
Using a hardware calibration device, the following have been set/measured:
1. Colour temperature = 6500K
2. Gamma = 2.2
3. White Level Luminance = 90 Candelas per square metre
4. Black Level Luminance = 0.26 Candelas per square metre
This page last updated in February 2010 by Kulvinder Singh Matharu
