5.2 Choosing a Monitor

If you decide to use a desktop rather than a laptop, you’ll obviously need to buy a monitor to go with your computer, and in fact even if you do opt to use a laptop, you may want to buy a monitor to use with your laptop (especially if your laptop has a small screen).  Large, bright, flat-panel monitors have become extremely affordable in recent years, and the use of widescreen monitors can be especially convenient when processing high-resolution images, since the added real estate of the larger monitor will allow you to view larger portions of the (zoomed-in) image at one time, while also leaving room on the screen for other information, such as the image’s histogram and the software’s tool palettes.

5.2.1 Monitor Sizes

Whereas most laptops have a built-in screen of only about 15 inches (measured diagonally between opposite corners), affordable external monitors now range up to 30 (diagonal) inches or more.  As mentioned above, such enormous screens are a joy to use when editing images, since you end up spending less time scrolling back and forth between parts of an image.  Given the amount of time some of us spend in front of a computer, anything that can make the process go faster is a godsend.  However, it’s important to keep in mind, when shopping for a monitor, that any model which is both extremely large and inexplicably cheap is probably inferior in some other way—i.e., in the pixel pitch (the size of individual pixels on the screen), the color rendition, or perhaps the overall construction and tendency toward component failure.  As with cameras and lenses, it’s usually wise to stick to the name brands when possible (such as Samsung or Sony), and to keep in mind that you get what you pay for.

Fig. 5.2.1: Life on the Big Screen.  A 30-inch monitor provides a truly vast amount of visual
real-estate.  With such a large portion of your image visible in the same window, relatively
little time is spent scrolling back and forth between critical parts of an image during intensive
editing.  This will become even more important as the megapixel race continues and images
with 30 million pixels or more have to be inspected and/or edited for publication.

5.2.2 Color Gamut

The color gamut of a monitor is the largest range of colors that it is capable of displaying at one time.  A limited gamut can result in a loss of subtle details in largely monochromatic parts of an image.  Laptop displays typically have a smaller color gamut than quality external displays, and this can, unfortunately, affect the way you process your images.  Using such reduced-gamut devices can mislead you into thinking that an image lacks details in particular regions, when in fact there may be details there which your monitor is incapable of rendering.  Conversely, if your monitor has a large color gamut but your printer does not, you may find that an impressively detailed image, as it appears on your monitor, does not appear quite so impressive when printed on your consumer-grade printer, since fine color differences used to represent some of the details in the image may not come through as distinct details in the printed image.  Also, other people viewing your images over the internet may see less detail in your images than you see when you view them on your larger-gamut monitor (or vice-versa).

5.2.3 Pixel Technologies

There are several different technologies in use today by manufacturers of flat-panel monitors, with different technologies being favored by different users, depending on whether they prefer better color or better response time.  The cheapest flat-screens use a technology known cryptically as TN, and though these are popular among the video-game crowd due to their fast response time, they have significantly lower color fidelity.  Indeed, when shopping for a wide-screen monitor, it may be best to avoid those monitors with the fastest advertised response times, since these are likely to be TN monitors (and since faster response times are essentially useless for static image processing).  Several technologies producing higher image quality are those currently known as IPS (sometimes called S-IPS) and VA (also called PVA or MVA).  Unfortunately, these acronyms rarely appear on product display cards in stores, though some clever Googling (e.g., including the model number and the letters "TN" or "IPS" or "PVA" as separate search terms) can often lead to reliable information on the underlying pixel technology utilized by a particular model.
    In terms of other advertised features of monitors, such as the viewing angle and the contrast ratio, some are likely of greater utility in image processing than others.  The viewing angles of just about all of today’s newest flat-panel monitors are more than adequate for the single user sitting directly in front of the monitor.  The contrast ratio is likely of greater concern, though again, the technologies used in flat-panel construction seem to have reached the point where contrast ratios are quite adequate for most models (with the possible exception of the cheaper TN models).

5.2.4 Monitor Calibration

Whichever monitor you choose, please make sure you properly calibrate it before you begin postprocessing your photos on it!  If by chance your uncalibrated monitor has any sort of bias
whether a color cast or an excess of brightness or darknessthen you will inevitably end up compensating for that bias during postprocessing, probably unconsciously.  As a result, your photos will end up having the opposite bias when viewed by others on their screens.  For example, suppose that your uncalibrated monitor renders images darker than it should.  When processing your photos in photoshop, you’ll have a tendency to over-brighten your images, to overcome the dark bias of your uncalibrated monitor.  When you post these images on the internet, other people viewing your images with a properly calibrated monitor will think your images are too bright.  You don’t want that.  Calibrate your monitor as soon as you get it, so that you can be sure that other people viewing your photos on the internet are probably seeing roughly the same image that you’re seeing on your monitor.  (Of course, those internet viewers won’t all be using properly calibrated monitors, but many of them will, and on average the uncalibrated viewers will be most satisfiedon averageby images that were postprocessed to look well on an unbiased monitor).
    You can do a quick check of your monitor’s calibration status using the calibration key below.  If any of the gray bars have a color cast, or if you don’t see all 10 bars as having distinct shades (particularly the two darkest bars and the two whitest bars), then you definitely need to calibrate your monitor.  More subtle biases require specialized software and/or hardware to detect.  Monitor calibration is discussed in section 14.1.2.

Fig. 5.2.2: Calibration key.  This simple strip of
gray bars can be used to diagnose obvious biases
in your monitor’s calibration, but for the best results
you really need to use calibration software to fine-
tune your system.  See section 14.1.2.