Excitement and Fear over Retina Displays

2012.11.03

Nine years ago, IBM delivered a display to my desk, the $27,000 USD T220. This is a 9 megapixels 22" LCD with a resolution of 3840 x 2400. Of course, being IBM, they did not have a cool name for it and they called it a QWUXGA for Quad Wide Ultra eXtended Graphics Array.

Compared to Apples's Retina, this is quite a mouthful but indeed but the IBM T220 had a resolution of 204 DPI. IBM claimed they had delivered this technology 10 years ahead of schedule and it seems the estimate is very close. The T220 was introduced in September 2003.

The T220 was an amazing display, it delivered crisp details like never seen before and was... quickly discontinued despite a price drop to $9000 USD. The problem is that technology has a hard time living in a vacuum and other components from 10 years in the future had not arrived yet! The first units ran at 40 Hz and required 4 DVI links, so we used two dual-head graphics card to drive it, which each head driving a quarter of the display. The setup was not pretty and moving images were choppy and everything looked minuscule. An amazing demo but not much of a sell.

Now computers are powerful enough and Apple was first out with ultra-high-resolution displays, up to 2880x1800 on a 15" laptop which equates to 220 DPI. Just last week, Google produced an even sharper display for its 10" tablet. This one has a 2560x1600 resolution - the same as my 30" NEC Multisync LCD3090WQXi-SV - but one third the size. I have not seen either in the flesh yet but it must be truly impressive!

It won't be much longer until more displays start appearing at those resolutions. Probably on laptops first since smaller displays have better yields and on independent ones after some time. This will give much more realism to images and provide a preview which is considerably closer to prints. Operating system support is needed to allow this to work with legacy applications and Apple has done this very cleverly. We'll see how Microsoft and Linux address this.

Unfortunately this is also bad news for photographers. Higher DPI onscreen means that more pixels have to be sent to cover the same area. To show a 4x6" print on-screen currently it only takes a 600x400 pixel image, or 0.24 MP. On a 300 DPI display, we need 9 times those pixels, so 2.16 megapixels. Scale that to 900x600 which gives a more comfortable size for appreciating images and you need to replace 0.5 MP images with 4.5 MP ones. This will sadly open more doors to people stealing images because they will be able to do more with them.

Reality is that images on the web get stolen and used without attribution not just by individuals wanting a cool wallpaper but commercial entities for their websites and even print campaigns. The advent of Retina displays gives those felons more ammunition. Of course one can still showcase image at lower resolution but viewers will see an image which is less sharp than others and most won't bother understanding why.

• Technology