Copyright © 2012 Kulvinder Singh Matharu. All Rights Reserved
This section provides a very quick and dirty way to adjust the
“brightness” or luminance of the screen/monitor (I
will be using the
words "screen”, "monitor” and "display"
interchangeably here), and was originally
put together as some people had reported that my images were too dark;
these reports were especially common when CRT monitors ruled the roost
in most people’s homes. Today, with LCD-type monitors, these
reports
are not so common. I think, to a large extent, that this is because
modern LCD monitors have crazy high luminance levels set as default
(200+ candelas per square metre or cd/m2).
Seriously, I have to squint to look at these monitors.
Monitor calibration is more than just about luminance levels; the
colours on the screen matter too. The common colour-standard for
screens is the so-called “sRGB” standard. The most
accurate way to get
correct colours and luminance levels is to use a device (e.g. a
colorimeter) to measure the light from your monitor allowing you to
calibrate and profile your monitor. Two colorimeters
that I’ve used are the Datacolor
“Spyder3Elite” and the x-rite
“i1Display2”. I’ve
posted my monitor
settings at the bottom of this
page. Note that I've set my monitor luminance to 80
cd/m2
which some people may consider too dark; some people recommend 90 cd/m2
or even 120 cd/m2. ISO 3664:2000 allows a
monitor
luminance from 74 cd/m2 to 100 cd/m2,
and the ISO 12646:2004 (which takes printer output into account) allows
a
monitor luminance from 80 cd/m2 to 120 cd/m2.
It
all depends.
However, I imagine that you’ve landed on this page because
you do not
have a hardware device such as a colorimeter and are seeking some help
in alternative means of adjusting your monitor. The steps below
describe a quick and dirty process for setting the luminance of your
monitor. However, I highly recommend that you visit
Norman
Koren's site and The
Lagom LCD monitor test pages as these offer
superior methods; if you are going to use those sites please make sure
that your web browser zoom settings are at exactly 100%.
OK then, let’s begin! Hopefully your monitor has controls labelled "Contrast" and "Brightness".
Ensure that the monitor has been switched on for at least 30 minutes. Also ensure that room-lighting is not too bright.
Most monitors today should have a setting that allows you to choose from a number of colour presets; choose “sRGB”. If you do not have such a setting, trying resetting the monitor to it’s default setting; this may or may not help! Once ready, we can proceed to Step 3.
FOR CRT MONITORS:
Set the monitor "Contrast" level control to the maximum value. If image
distortion occurs or if the screen seems too bright then lower
"Contrast" level until the distortion is reduced. Note that CRT
monitors can
exhibit severe geometric distortion at high "contrast" levels.
FOR LCD MONITORS:
LCD 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 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.
This step is all about adjusting the black-level. Starting from a "Brightness" level of 0% (i.e. 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 blackest bar as black as possible (so that blacks appear black on photos) but still be able to differentiate between adjacent bars.
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 ease.
I have found that a number of LCD 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!
Remember, the steps listed above are quick and dirty.
If it helps anyone (and each monitor is different and subject to ageing), I use two Dell UltraSharp 3008WFP 30-inch monitors in a dual-monitor configuration on my Windows 7 Ultimate 64-bit machine. Each monitor's settings are listed below; these settings are currently suspect as I've just recently switched between colorimeters and the luminance appears much higher than what I've been used to using the previous colorimeter. The colours appear fine but that's another story though!.
| Monitor 1 | Monitor 2 | |
| "Brightness" monitor control | 38% | 35% |
| "Contrast" monitor control | 50% | 50% |
| "Red" monitor control | 75% | 75% |
| "Green" monitor control | 71% | 71% |
| "Blue" monitor control | 83% | 83% |
| Colour temperature (or "white point") | 6500K | 6500K |
| Gamma | 2.2 | 2.2 |
| White level luminance (cd/m2) | 80 | 80 |
| Black level luminance (cd/m2) | 0.2 | 0.2 |
And here are the monitor results:
There may be a colour preset in your monitor controls to select "sRGB" mode. Do that. However, I find that on my monitors that this "sRGB" mode is not really that close to sRGB. But it may work for you.
Your graphics driver may have an adjustment to change colours, gamma, etc. On my machine, I can use the "Nvidia Control Panel" to reduce "Digital vibrance" from 50% to 40%. 40% seems a decent match to sRGB; your mileage may vary. It ain't perfect, and I do recognise it as a kludge. Please note that you should have calibrated the display to 6500K and gamma 2.2 before making these adjustments in the "Nvidia Control Panel" or its equivalent. Once this is done, you should then remove the monitor colour profiles or select an sRGB profile in your OS's colour management control panel.
Windows 7 tip: if you're having difficulty locating the Windows "Color Management" control panel or the "Nvidia Control Panel" then use the "Windows Search" tool. "Windows Search" is accessed by either pressing the "Start" button or pressing the Windows key on your keyboard. Then just type "col" or "nv" (without the quotes) and then select. I find I'm using this feature a lot as I just don't want to waste my time memorising where all the software, apps, tools, etc are located.
I'm sure that there may be other options dependent upon your hardware/software configuration. You'll have to decide what works for you. And good luck!This page last updated on 11th September 2011 by Kulvinder Singh Matharu
