Producing a proper world map (globe)

[Iggy]

I've been struggling how to produce a globe world map in Photoshop CS6 that uses a world projection type. I've read a thing or two around here, particularly this thread on map projections, brought to my attention in the topic where I posted my world map which doesn't use a world projection, but it still evades me how I can paint landmass on top of the provided templates that follow the curves of the world projection as pointed out in this post. Other programs like Flex Projector came to my attention through here as well as Quantum GIS and G.Projector but do I need to use these or is Photoshop all it takes? Sure, with Flexify 2 I can easily transform a flat land map into a globe in Winkel Tripel but I don't see how that brings me any closer in making a proper globe map.

Photoshop tutorials I have seen so far do not cover the subject of world projection so those are not helpful.

I need a proper map for a fantasy novel I'm working on, I could resort to a complete flat land but I would rather have a (proper) globe world. I need to get the geography right before I continue.

[Azélor]

Do you mean an orthographic projection? Orthographic projection (cartography) - Wikipedia, the free encyclopedia

It would make your world look like a globe seen from space just like earth.

[Iggy]

Yes. I was pointed out to at least use a world map projection type, the exact how to do this still evades me after doing some searching around on it hence this topic.

I feel as I've seen all pieces of the puzzle but how to put it together is still not clear to me.

[Azélor]

Do you plan to keep your already made landmasses ?

[Iggy]

It is no problem if I have to make it all over again.

[Azélor]

Ok well then if you paint your map using a layout what is the problem ?

Personaly, I made a world map before thinking about the projection. It seems to be equirectangular, but even so, I'm not sure. If I want to, I can say that it's Hammer or mercator as long as the world fit the layout and the climates remains similar.

[Hai-Etlik]

I can easily transform a flat land map into a globe in Winkel Tripel but I don't see how that brings me any closer in making a proper globe map.

I think you've got this a bit backwards. The "real" shape is a globe, as in a 3D, close to spherical shape. Any map is a distortion of the globe because it's flat, while the globe is not. The particular way that flattening is done is the projection.

You can think of it as if you put a light at the centre of a clear sphere with the features painted on the surface. Then held a flat piece of paper up to the globe, and traced out the shadows cast on it. This particular projection is called Gnomonic and it's used in geology, and for building projections on the surfaces of polyhedra. Other projections role the paper into cones or tubes, move the light, or even bend the light or do other strange things.

So don't think about drawing a flat map and then putting it in a projection. Think about drawing in a projection, and then changing to another projection. You need to draw the distortion for the first projection into the map otherwise when you change projections, you'll get the reverse of that distortion combined with the distortion of the second projection. Even if you stick with the original projection, you still need to get that distortion right or the map will look wonky to anyone familiar with real maps.

One thing to ask yourself is, just how much area does the map need to cover? Do you really need a map of the whole globe? Smaller extents are easier. You still need to think about where you are on the globe and pay some attention to projections, but it's a lot easier. You should also think about what kind of map it is and what level of cartographic and surveying sophistication was employed. It might be that dropping things you are used to seeing on modern maps like graticules, compas roses, scale bars, or even trying represent the spatial relationships between things at all will make your life easier. In the times most fantasy draws on, maps were fairly rare, and tended to be more topologocal than topographic; they were about connectedness rather than shape and distance, more like a modern subway map. They also had very poor source material to work with.

[Iggy]

So don't think about drawing a flat map and then putting it in a projection. Think about drawing in a projection, and then changing to another projection. You need to draw the distortion for the first projection into the map otherwise when you change projections, you'll get the reverse of that distortion combined with the distortion of the second projection. Even if you stick with the original projection, you still need to get that distortion right or the map will look wonky to anyone familiar with real maps.

Can I do this with just Photoshop CS6 or do I need some of the other applications I named in my openings post?

One thing to ask yourself is, just how much area does the map need to cover? Do you really need a map of the whole globe? Smaller extents are easier. You still need to think about where you are on the globe and pay some attention to projections, but it's a lot easier. You should also think about what kind of map it is and what level of cartographic and surveying sophistication was employed. It might be that dropping things you are used to seeing on modern maps like graticules, compas roses, scale bars, or even trying represent the spatial relationships between things at all will make your life easier. In the times most fantasy draws on, maps were fairly rare, and tended to be more topologocal than topographic; they were about connectedness rather than shape and distance, more like a modern subway map. They also had very poor source material to work with.

I would greatly prefer it to have a good world map of my realm. It needs to show locations of capitals, borderlines of kingdoms and I should be able to calculate the distance between two points so I can determine how long my character's travel should take. I will make maps of smaller regions based on it later. I know that some fantasy authors such as J.R.R. Tolkien and David Eddings started their projects with a map (heck, Edding's entire fantasy career started with a map!) and both advise to get your geography right.

Ok well then if you paint your map using a layout what is the problem ?

Personaly, I made a world map before thinking about the projection. It seems to be equirectangular, but even so, I'm not sure. If I want to, I can say that it's Hammer or mercator as long as the world fit the layout and the climates remains similar.

I simply don't know how. If drawing land mass on top of a template such as this is a good way to start, how does one do this in Photoshop? Alternatively, if I have a flat land, how do I add the right distortion for the projection type I want?

[waldronate]

The ultimate cheat to avoid confusion about projections is to go to your local thrift store and buy a used globe. They're usually pretty cheap, at least around here. Then spray paint it flat white and draw on its surface to rough things out. From there, you can stitch together and reproject a few pictures to get an image in something like the Equirectangular projection.

If you're intent on doing a digital-only map, try using a template like the one you referenced above. Load it into Photoshop and resize as appropriate. Then make a new layer and draw onto that. Once in a while, use a program that supports reprojecting images like G.Projector to see how your map looks in other projections. Drawing in the distortions digitally can be a bit confusing because of how the grid lines converge toward the poles.

Ideally, you'd use a paint program that has an understanding of projections, but I haven't run across a good and easy-to-use one yet. If I'd ever get things in gear and add projective brushes to Fractal Terrains, it would be close to suitable for this use. As it is, FT does make viewing things in various projections a little easier, if not exactly correct.

As far as reprojecting your flat map into a world map, it's a matter of what you already have. If your continents are reasonably equatorial, you can probably just select an existing projection like Mollweide or Hammer and declare that your map is defined in that projection (any distortions around the edge are likely to be far away from the primary area of interest along the central meridian and you can simply say that they are due to cartographic error).

[Iggy]

Thanks for the suggestions, I'll try out some tricks. I also found this PS plug-in called Spherical Mapping Corrector that might help with creating the right distortion.