Relief mapping in 10 easy steps!

Try it at home! Satisfaction guaranteed!

Continuing our recent theme of terrain-related side projects, a few days ago I finished (or, decided to quit working on) a shaded relief map of New Hampshire's White Mountains that I'd been pecking at from time to time for a few months. Most of our work is with interactive, web-based maps, and although we occasionally get to do more traditional static cartography (with hillshades, even), sometimes the kind of slow, singularly designed cartography we remember from our pre-web days has to be done just for fun.

It's satisfying to see a map come together piece by piece, as in the above animation showing the main steps and layers in producing this map. Cartography is rarely a matter of throwing data into software and getting a map in return; rather, a single map usually involves multiple tools and data sources, and a lot of attention to small details. (The same is true of web maps, by the way: we write a lot of code for small design details that push beyond defaults.)

There's no single way to make a shaded relief map, but here's how this one came together:

  1. Download a good digital elevation model from the National Map.
  2. Genereate a shaded relief image using Blender, per Daniel Huffman's excellent tutorial.
  3. Set up a QGIS project with land cover data. Reduce it to only a few colors (mainly, evergreen forest and "everything else") and export it with dimensions matching the relief image.
  4. In Photoshop, add land cover, then the relief layer with a "multiply" blending mode.
  5. Heavily blur the land cover so that it's not harsh and pixelated. It becomes a subtle base layer, not an essential piece of data.
  6. Add water lines and polygons (via Census TIGER/Line) to QGIS, style, export, and add to Photoshop above land cover.
  7. Use some Photoshop tricks to make relief highlights a bit brigher and warmer-colored, and shadows a cooler color.
  8. Generate and label contour lines from the DEM using QGIS, then export and add them as a Photoshop layer.
  9. Add roads (from OpenStreetMap via Geofabrik's extracts) to the QGIS project. Export and style them with Illustrator, and place the .ai file as a layer in Photoshop underneath the relief. (Shadows thus fall on roads as they would in real life.)
  10. Label all the peaks, physical features, and towns one by one in Illustrator (no GIS data involved), and place them into Photoshop.

Then just a bit of cropping and cleanup, and it's done! That list, of course, vastly oversimplifies things, but it gives a good idea of everything that goes into a map. Labeling, for example, is hugely important and takes a lot of time to do right.

Perhaps my favorite touch, briefly visible in the animated sequence, is number 7 from the list above: adding extra punch to the relief map's highlights and shadows. Daniel Huffman also covers something like this (along with much more!) in his walkthrough of terrain mapping in Photoshop. A brightened, warmer tone is applied to the light side of mountains at high elevations, while shadows are given a blue tint. Not only does this seem to boost the illusion of depth, it also better evokes the temperature and appearance of a warm sun and cool shadows in reality. The effects are applied lightly, but they make a difference.

It's been fun to practice this kind of cartography and learn new things along the way (Blender is great!), while more deeply studying a region that is somewhat dear to me. Here's the full final product.

Related Project:

No items found.
From the Blog