Adobe Photoshop CS5 for Photographers - Martin Evening [46]
Wide dynamic range displays
It is interesting to speculate what computer displays will be like in the future. Dolby recently acquired BrightSide Technologies who developed an LCD display that uses a matrix of LED lights instead of a fluorescent light source to pass light through the LCD film (Figure 2.2). These displays have an incredible dynamic range and are capable of displaying a 16-bit per channel image with an illumination range that makes an ordinary 8-bit display look dull and flat by comparison. We may one day even see display technologies that can get closer to simulating the dynamic range of natural light. These will be great for viewing computer games and video, but for Photoshop print work we will want the display we are looking at to match our expectations of what can be reproduced on a print.
Figure 2.2 This shows the Dolby DR37-P 37″ wide extended dynamic range screen.
Adding a second display
To run a second display you may need to buy an additional video graphics card that provides a second video port. You can then have this located alongside the main display and use it to contain all the Photoshop panels and keep the main screen area clear of clutter.
Video cards
The graphics card in your computer is what drives the display. It processes all the pixel information and converts it to draw the color image that's seen on the display. An accelerated graphics card enables you to do several things. It allows you to run your display at higher screen resolutions and hold more image display view data in memory, and it uses the display profile information to finely adjust the color appearance. When more of the off-screen image data remains in video memory the image scrolling is enhanced and this generally provides faster display refreshes. In the old days, computers would be sold with a limited amount of video memory and if you were lucky you could just about manage to run a small display in millions of colors. When you buy a computer today the chances are that it will already be equipped with a good, high performance graphics card that is easily capable of meeting all your needs. A video card will probably have at least 256 MB of dedicated memory, which is enough to satisfy the minimum requirements for Photoshop CS5. However, with the advent of the latest OpenGL features, it is now worth considering video cards that were previously considered only necessary for gaming and 3D work. Check the Adobe Help site to find out which cards are designated as being compatible for Photoshop CS5 and OpenGL.
Which video card is best?
If you do want to take advantage of what OpenGL can offer in Photoshop, it might be necessary for you to purchase a new video card. At the time of writing, there is a long list of the video cards that are capable of providing OpenGL support in Photoshop CS5 for Mac OS X 10.5 (or later), Windows Vista and limited support for Windows XP and Windows 7. Adobe do list the GPU cards that are recommended for Photoshop use, but it is difficult though to point to any one group of cards and say these are best. This is because the OpenGL performance in Photoshop is down to not just the card, but also the computer platform and operating system used. For example, a great many Mac Pro users such as myself will have been using NVIDIA GeForce 7300 GT video cards to drive their displays. These were the default cards Apple installed for a while. Although the 7300 GT is regarded as being compatible with Photoshop CS4 and CS5, they happen to perform OpenGL tasks rather poorly. Therefore, the impression gained by a lot of Mac users has been that OpenGL isn't particularly fast. Fortunately, the later Mac Pro computers