Thread: Fresh start with continental map

For a high latitude small scale map like this, you're definitely going to want to get an idea of your projection and extent early on. This isn't something that can easily be fudged under these conditions.

Given it's roughly the same extent as Canada, I'd suggest taking a map of Canada in a Canada specific projection and using that as a template. Statistics Canada Lambert Conformal Conic (EPSG:334 is my usual choice of projection for maps of the whole country. (As in this map Picture 1 of 5 from Contest Entries)

I was afraid someone would call me out on that, I just hoped it would not be within 30ish minutes. Yeah, I am terrible at the math involved, so I try to wing it. I did throw a Canada map in as my reference layer, though, for that very reason. This is the grid they used:



Looks similar to what you use, at least to my very untrained eye.

As an aside, is there an easy way to convert that sort of thing back to Equirectangular?

Originally Posted by bartmoss

I was afraid someone would call me out on that, I just hoped it would not be within 30ish minutes. Yeah, I am terrible at the math involved, so I try to wing it. I did throw a Canada map in as my reference layer, though, for that very reason. This is the grid they used:



Looks similar to what you use, at least to my very untrained eye.

I wasn't trying to "call you out", I was just pointing out that this was something that could bite you if you weren't wary. For instance, you can't put a compass rose on this map. I wasn't saying that you need to include a graticule for instance just that if you do, it needs to be a fairly specific one.

They are both Conic projections, which is fairly typical of maps of this extent and position and is why they look similar. I'd need to look at how the graticule distorts as you move away from the standard parallels to make a guess as to which particular conic projection it is.

Originally Posted by bartmoss

As an aside, is there an easy way to convert that sort of thing back to Equirectangular?

If you're working in a GIS from the start, yes, but then you probably wouldn't be asking. With plain graphics tools, no, not really as it requires georeferencing the image, which is tricky unless you stick to normal aspect cylindrical projections (which this is not).

That's why easy tools like G.Projector can't do inverse transformations. Also, some projections don't have closed form inverses which means you have to use complex, slow, and inaccurate numerical methods to reverse them even if the image is georeferenced. The commonly used conic protections do have closed form inverses though.

PS: Here it is in Plate Carree/Equirectangular The georeferencing isn't the greatest and it lost a lot of resolution in the process

Oh don't get me wrong, I didn't take it in a bad way - I meant "called attention to the shortcuts I am taking". I very much appreciate constructive critcism, always.

The Equirectangular projection (thanks for doing that) looks... weird. Not really unexpected, I guess. if I take one lesson from this, it's that I should work in euirectangular again in the future but always check the map in other projections and on Google Earth (nice and easy interactive sphere) - I did the later for some maps and it really helped reign in the worst problems near the equators.

I do wish GIS software was more... accessible. It seems any serious world building project really should use GIS, but it's just so much easier to just whip out Inkscape and get going...

And I figure I should probably add the "latest" WIP - it's been a while since I touched this map.

Very nice, I wouldn't have the patience for all those elevations.

Looking nice! This something I'm keen to try, but it looks like slow work.

I like it. When do we get to see rivers and waterways?

actually, looking at it again, i wanted to ask, will you be adding any more levels of elevation? maybe between existing ones or above the high mountians? there's room for more if you want to get more detailed