The Display Dilemma
By David Crowther
Do you monitor your Display or display your Monitor?
If you are any of the above, no doubt you usually commence working visually with images. A properly calibrated and profiled display is imperative. The computer display can be the most unstable part of a colour management system (CMS), and often, not enough attention is given to the importance of selecting the right display for the job, and then maintaining its colour output consistency.
I am constantly astounded when speaking and consulting on site with imaging professionals, finding that they have skimped on their display system or worse, failed to properly implement good colour management for this vital piece in the puzzle. For example: to the professional photographers amongst us, when you made that all-important decision to go digital, your choice of SLR would surely have been influenced by which manufacturers lenses were in your equipment case. I.e. if you had a bag full of Nikon gear and lenses, rather than reinvest in complete new kit, you would probably check that your new Nikon digital SLR body could use all your existing Nikon lenses. A good lens is the key to quality digital capture and many photographers swear by their lenses. And (the key point), you always invested heavily in a high quality lens. You never skimped on lenses - image quality was No.1! It makes sense then, that with all of your creative abilities at stake, display choice and controlling its colour quality should be at the very top of your priority list in your workflow.
True, everyone has a price in mind or a budget to stick to, but it can be truly said of computer displays that you get what you pay for. Quality is remembered long after price is forgotten. In our colour management courses, we always try use a variety of CRT and LCD displays together with different calibration software to demonstrate this point.
To get out of the display your monitor mentality, you have to start monitoring your display.
If you already have a display that you are happy with, what can I do and where do I start? PhotoShop will not display your image correctly if you do not have an accurate profile for your device. To make a monitor profile you need profiling software, which can be divided into two camps: those that use measuring instruments and those that do not. Simple utilities such as Adobe Gamma and ColorSync Display Calibrator can create a monitor profile without a measurement device. Reliance is thus placed on the user to make visual adjustments. The results are subjective and therefore, not repeatable. Accurate monitor profiles require commercial profiling software that uses a measurement device, such as a spectrophotometer or colorimeter.
Theoretically, any display can be profiled, but the accuracy and stability of the calibration is governed by the choice of display.
Configuring a display system for accurate colour managed viewing can be achieved at a fairly low cost. Monitor profiling packages range from about $200 anywhere up to $1000 and are relatively easy to implement. Compared to profiling other devices, monitor profiling requires little input from the user. There are no charts to scan or print; rather, the user simply follows a series of on-screen steps and instructions. The biggest task to making a good monitor profile is knowing how to make adjustments and what settings to choose. When you begin, you are usually confronted with making choices for white point, luminance (white and black) and gamma. These can be considered the calibration settings prior to the software going through the profiling process. Making the adjustments to meet the desired settings means familiarising yourself with your monitors controls and the on screen display (OSD). You will need to make adjustments to brightness, contrast and even individual RGB output, and even then the instructions from the software sometimes do not seem to make sense. If you know what the software is trying to get you to do, you can then make informed decisions. Sometimes it is best not to be totally dependent on particular vendors uncertain or confusing instructions.
At Chromaticity, we constantly preach that the key to any good profile is calibration. Calibration provides a known, measurable and repeatable state for a device (e.g. monitor, scanner, camera, printer, etc.) Often the line between calibration and profiling a display is unclear, with some profiling packages limiting the options and some displays offering limited adjustment. For example, does your monitor have manual adjustments or controls for brightness, contrast, individual RGB gain or output? What should be the aim points? Gamma 1.8 or 2.2? White point, 5000K, D50, D65, 6500K, 9300K or Native white point? Luminance (maximum intensity of white) measured as candelas per metre squared, 85 cd/m2 or 100 cd/m2 or 140 cd/m2 or something different entirely? Black luminance .25 cd/m2 or something different entirely? Unfortunately, we do not have enough space here to thoroughly discuss the pros and cons of each aim point, but suffice to say that I am usually loath to recommend monitor calibration aim point specifics without first establishing parameters like ISO 3664:2000, ISO 12646:2004, ambient lighting, studio conditions, monitor age and the rest of your colour managed workflow.
You may like to note that the emergence of high end LCD displays with TFT (thin film transistor) technology using a LUT (Look up table) inside the display to look after calibration provides improved control and greater stability over longer periods, reducing the need for recalibrating and profiling from days to a month or more.
The benefits of a properly calibrated and profiled display are numerous. You can soft proof images, accurately seeing how they will look in a CMYK press conversion, or predict how your digitally captured images will look for photographic output on inkjet canvas, gloss photographic or matt fine art media. Retouching and image enhancement can be carried out with confidence, saving you time and dramatically reducing print media wastage by breaking the vicious retouch-print-view, retouch-print-view cycle.
You can see that display calibration and profiling need quite a bit of detailed explanation but, as visual creators, we really do need to pay close attention to it. To achieve and maintain predictable, consistent colour, imaging professionals should feel a responsibility to start monitoring their display and learn to embrace the benefits of colour communication.
David Crowther is the manager of Chromaticity Australia. Chromaticity Australia offer colour management training and consulting.