All projections cause distortion. In my opinion, equirectangular is the most straightforward to make, especially for a beginner, and it can easily be converted to other projections by a free software program.
NASA GISS: G.Projector — Global Map Projector
With this, you don't have to estimate the enlargements at the poles or the distortion of the continents. It will convert a map that is in a 2:1 ratio to many well known projections.
Now, how technical do we want to get? If we just want to show the continents and the relative distances between them, you don't have to do much else. Just be aware, as I said earlier, that the areas at the poles will not be 100% accurate. That's not too bad if you don't have much in those areas.
If you want to be totally accurate, there are ways to correct those polar regions. I use Photoshop. I'm not sure if Gimp has the same function, but here's what you do.
1) Take your equirectangular map and use Photoshop's polar coordinates filter to make your rectangular map into circular ones with the poles at the center, just as you see above.
2) Use whatever tools you're comfortable with to blend textures, move lines, and adjust things at the poles so that they don't have that pinched centerpoint.
3) Now run the filter again, but in reverse, from polar back to equirectangular.
4) Your new equirectangular map now shows the areas at the poles properly stretched so that when you apply the map as a texture onto a sphere in a 3D program, everything will look correct. The continents will narrow as they get closer to the poles, but at least things won't converge in a point.
Awesome. I kind of thought all projections would have distortion. Its really strange to convert a 3D sphere to a 2D rectangle. However, that is an awesome idea. And I KNOW I saw a similar Gimp tutorial somewhere around the internet. Off to that now, will return later with my attempt and more questions for my next step. *walks off, mumbling to self and digging through hoarded tutorials*
Probably the most robust way to handle this would be to use a GIS like QGIS, and block in roughly where you want things. Then create appropriate regional projections for each region and work on the details of each region separately. This would be dramatic overkill but it is the "best" solution as it uses the real world tools used for managing geographic data.
If you don't need to do a full globe, restricting yourself to a smaller extent will make things a lot easier, particularly if you stay away from the higher latitudes.
If you want relatively easy compatibility with G.Projector (which is a lot easier for people with only a graphics background than a full on GIS) then you can get a regional projection that you can still feed into it. Pick a bounding box in latitude and longitude. Then cut out that portion of your plate carree map. Then scale the image horizontally by cos(latitude) for a latitude in the box.
For instance, the cosine of 45 degrees is 1/sqrt(2) So if the 45th parallel runs through the middle of your map, you can squash it by 1/sqrt(2) to get something that is less distorted within that box. Edit to add your details, then you can stretch it back out by sqrt(2) to get back to the plate carree projection again and put it into your world map. Then you can use G.Projector to put it into a projection suitable for a finished world or regional map. (Don't do any fancy styling or graphical work until it is in the final projection.) Obviously, the taller the box, the less well this works.
So I downloaded G.Projector and QGIS. At first glance and toying around with it, G.Projector is great, and QGIS is...well, @_@. Lol, it looks like a great tool, but I'm not sure how to achieve what you're describing, Hai-Etlik. So I'm basically just trying to re-proportion the more northern parts of my landmasses, yes? I guess I just need direction as to where to start (importing my map to QGIS, or choosing the best projection from G.Projector and going from there). I think once I get the basics down, I can get something reasonable and come back here, though it may take some time.
And so, once I get the landmasses in order, I'll get that up here and work from there on the next step. Hopefully. lol
Yeah I only mentioned QGIS for completeness. I should have been more clear that I didn't really expect you to use it, just that that was the kind of tool you'd need if you really wanted to be really precise about this. Trying to draw the correct distortion into an equidistant cylindrical map by eye is probably your best bet. Draw your shapes, load the map into G.Projector, and take a view of the poles. I'd recommend using the Stereographic projection and setting the latitude to 90, or -90 (depending on which pole you want). See if it looks wrong, and if so, go back to the original equidistant cylindrical map and try to correct it, then load it back into G.Projector to see if it worked.Originally Posted by okami
Ah, I see! Do I make the changes to the the map in a different program then? I'll start getting on that.Thanks!
The workflow would be similar to software development or web design. Edit, then run it through a process to see what you get, and then go beck to edit the original.
Edit the map in your graphics editor, then load into G.Projector, pick Stereographic and set the latitude to +/- 90. Look at the polar aspect maps that result and decide what changes you need to make to correct any problems. Then you have to go back to editing the original map in your graphics editor and make the corrections. Try to make small incremental changes rather than adding a lot of detail at once and then trying to fix it.
Sorry I haven't been here lately! Spending time with family for the holidays and getting into school for the past few weeks, but I'm back again.
Anyway, I made some tweaks to the map and the plate boundaries.
New Map
North and South Poles
New Map with Plates
North and South Poles
Oh I like the tectonic plate changes you've made. There's a clearer view of oceanic plates and continental plates. Remember that oceanic plates tend to subduct, or slide under any land plates they collide with thereby generating your island arcs or volcanic mountain ranges.
Yay!! Thanks so much for you and Hai-Etlik's help.After I nudge some lines off the edge of two of my continents (which I just noticed and now it's bothering me. >_<), I believe my next step will be terrain height and climate.
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