Pixels or Perish
The art of scientific illustration will have to adapt to the new age of online publishing
Gains and Losses
Interactive gadgets like the Web version of the population pyramid tend to be put in a category apart from the illustrations that appear on the pages of a magazine or journal. They are classified as supplemental material, or maybe educational software, and are not seen as an integral part of the publication itself. Years ago, many publishers segregated photographs and certain other kinds of illustrations in an analogous way. They were printed on special paper and bound in a separate section of “plates.” That practice ended with improvements in printing technology. Likewise, when publications are distributed over the network and read on a computer screen, active graphics can be integrated into a document in the same way that ordinary photographs and drawings are. There’s no reason to keep them out of the mainstream.
What do we stand to gain in going from paper to pixels? Animation—adding a time axis to a graphic—is the most obvious possibility, but there are many other ways to exploit the power of computation. For one thing, we are liberated from the fixed size of the printed page. Computer displays also have bounds, but when a figure is too large to fit, we can roam about in it by scrolling or by “panning and zooming.” (Think of Google Maps.) When a diagram is too intricate for the reader to see all details clearly, we can offer tools to magnify selected regions. In a cluttered graph, we can highlight and label data points when the reader selects them, or else hide distracting features from view. We can offer the reader options, such as changing the scales of a graph from linear to logarithmic, or choosing a subset of the data. Three-dimensional graphics are easier to understand in a medium where the reader can rotate a diagram or change the point of view.
Of course good old-fashioned paper also has advantages, starting with the fact that everyone knows how to use it. No one needs an instruction manual for reading a magazine. No one needs any special hardware or software, either. Authors and publishers can be reasonably certain that all readers will see the same words and pictures; there’s no need to worry that Internet Explorer will show one thing and Firefox another. And the printed page still offers a level of resolution and typographic refinement that cannot be matched on the electronic display screen.
At a deeper level, the producers and consumers of printed graphics have had many decades to develop conventions about various graphic devices and what they mean. For example, arrows are variously used to show the flow of material or time or interconnections between parts. Line graphs and bar charts have an elaborate semantics that is not obvious but is widely understood. Much of this knowledge and lore will transfer directly to new computational media, but we’ll doubtless also need some new graphic metaphors, and it may take time for them to emerge.