Sunday, April 8, 2012


Some choices are an advantage. You can select a digital camera from many that suit your needs and are within your budget, and likely get good quality image results. Almost as many choices are available for computer applications that support editing and processing digital camera image files for both Windows PC’s and Apple Macs, and they will get the job done effectively for most users. But when it comes to how to manage, and adjust a computer display screen for photography using an application like Adobe Elements or Lightroom and how to do it, the internet is full of imagined options and short on reliable facts.
If you run a Google search on a workspace profile name like Adobe RGB (1998), which is a pretty well known term now because advanced digital cameras can be set to save in Adobe RGB, you might expect an understandable explanation in an Acrobat .PDF document published by Adobe. I doubt you will get past the first couple of pages before giving up. If you don’t have an understanding of advanced physics the formulae are a mystery that explains nothing to most ordinary photographers, might as well open a text on trigonometry for entertainment.
But then if you get into some of the internet forum discussions about color management and display calibration and profiling, you might find questions from many users whether they should set their display to Adobe RGB (1998). The simple answer is no, and the reason is Adobe RGB (1998) is a workspace profile for Photoshop and many other Adobe applications to use internally, it’s not a display profile. But in an hour of reading I only found this information by chance, deep into a lot of extraneous discussions.
Some of the readers who are aware of color management as it applies to displays, ask what color temperature (white point) to use, and what gamma setting, realizing there are a lot of options. But are there really, even though some users employ various different settings? Today these are false and misleading choices for most photographers using a computer. Present computer systems like Windows and Apple have conformed to one standard gamma of 2.2 and a color temperature of D65 or 6500K. So lets just look at these basic settings as they are applied to todays LCD displays for computers. 
Even though some computer users still select the old Apple standard of D50 or 5000K, and gamma 1.8 they have their reasons, maybe that the display color temperature should match the color of the working environment. Many have installed D50 work area lighting. So I have to ask if D65 on a display looks too blue in D50 environment light, maybe it would be less costly and difficult today to replace the environment lighting, in the old days there weren’t any options, but today there are. But I am afraid people are inclined to hang onto what they are used to and resist change.
However technology changes, and one standard that applies to LCD displays now is that the backlight for the screen is 6500K. So if a user wants 5000K or D50 instead that shift has to be made in most cases by the resources in the computer’s video card. (Eizo Coloredge displays excepted, as are NEC Spectraview models.) Maybe that capability for the rest should be kept free for more important functions. Personally I changed the room lighting in my lab to LED lamps that last a very long time and use little electricity while producing an even amount of light of a color temperature that closely matches my LCD display’s backlight. It was easy to do and the price was a very small fraction of what an LCD display costs.
The other specification some insist they have to modify is gamma. The standard 2.2 some argue does not reveal enough detail in dark areas of subjects. Well there is an option in most display management software aim points, and that is to raise the black luminance to a slightly higher value than minimum. That will then be a part of your display profile and set the reproduction of the darkest black in an image a bit higher on the physical range of values the display reproduces. This will make what is in shadow more easily seen on screen.
Yes I am arguing for conformity to standards, a bit regimental for some Americans comfort likely. But there are good reasons. One is that many photographers will use an Adobe or another application from Corel or Lasersoft SilverFast that are color managed. And adobe, the most popular, in its Color Setting asks you to select a working-space profile for RGB editing like Adobe RGB (1998) or sRGB, which are used by many of us. Working space profiles impose their built-in settings on the display of images on screen. On launching the application whether Elements or CS5 Photoshop, the application references the default display profile so it can adjust images to the working space profile’s dictates, and in the case of sRGB and Adobe RGB the gamma is 2.2 and the color temperature (whitepoint) is 6500K. So If you have chosen a different white point and gamma it is essential that you select a working space profile that coincides with your gamma and white point choices if you want to work with Adobe applications and have your images accurately reproduced.
With Apple Macs their applications like iPhoto and Aperture work in display space, and if you save a TIFF file the display profile will be embedded in the file. This doesn’t help anyone else who receives the TIFF file because it is unlikely they can duplicate your display and its profile. So with Apple you have the ability with the Colorsync utility to convert the image to Adobe RGB (1998) and then it will be the image’s embedded profile. In other words color management is designed by Adobe’s implementation, and Apple’s to share image files with others computers, and they can reference the embedded profile and display the image as you saw it with your system to the extent hardware differences allow.
There are good and broad beneficial reasons to adopt standards, besides making life a bit easier on yourself,

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