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Printing a wall-sized world map and what I've learned from it

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Re: Printing a wall-sized world map and what I've learned from it

#61

Post by allemagne »

mewo2 wrote: post #34
dietrichepp wrote: post #7

This guy "loves world maps" but chose Mercator for the wall of his room? I guess there's no accounting for taste. There are hundreds of projections to choose from, why choose the one optimized for navigation by compass ?

I can't believe I'm doing this, but I think I'm going to defend Mercator here. The Mercator projection was indeed originally designed for compass navigation, but the reason it's still used for web mapping is slightly different. The Mercator projection is conformal . What this means is that angles (and hence in some sense shapes) are preserved locally. When we zoom in on a small section of the Mercator projection, we…

>The Mercator projection was indeed originally designed for compass navigation, but the reason it's still used for web mapping is slightly different. The Mercator projection is conformal.

Just speculating here, but it's also a big rectangle that is easy on the eyes. Non-rectangular online maps would fit awkwardly in websites. As for Gall-Peters, that map is just irredeemably ugly to me, and I'm ignorant of other rectangular projections that could compete with Mercator.

Re: Printing a wall-sized world map and what I've learned from it

#62

Post by Someone1234 »

lazyant wrote: post #41

National Geographic mural map is pretty decent (but yes, it's heavy on borders) http://shop.nationalgeographic.com/ngs/product/maps/wall-map...

Be careful the National Geographic online store sell their customer's information to marketers. Source: They did it to me.

If you want to opt out you'll have to send a physical letter to a specific address which is only found by clicking "Privacy & Security" then clicking "Privacy Policy" then "complete Privacy Policy" and final in the section called "V. Your Choices"

However they note that even sending this letter may do nothing:

> Because we plan our communications in advance, it may take several weeks for your request to become effective. If you continue to receive our communications in error after expressing an opt-out preference, please let us know so that we can investigate the situation.

And by that "few weeks" they likely have already sent your personal information to "other selected third parties" making the entire exercise pointless.

I love how intentionally misleading their "Privacy & Security" page is. And how even if you click "Privacy Policy" you just get a summary page which is equally misleading. You have to go down three layers to find the legitimate policy which sets out all of their scummy practices.

Re: Printing a wall-sized world map and what I've learned from it

#63

Post by mewo2 »

allemagne wrote: post #61
mewo2 wrote: post #34

Earlier quoted context omitted.

I can't believe I'm doing this, but I think I'm going to defend Mercator here. The Mercator projection was indeed originally designed for compass navigation, but the reason it's still used for web mapping is slightly different. The Mercator projection is conformal . What this means is that angles (and hence in some sense shapes) are preserved locally. When we zoom in on a small section of the Mercator projection, we…

>The Mercator projection was indeed originally designed for compass navigation, but the reason it's still used for web mapping is slightly different. The Mercator projection is conformal. Just speculating here, but it's also a big rectangle that is easy on the eyes. Non-rectangular online maps would fit awkwardly in websites. As for Gall-Peters, that map is just irredeemably ugly to me, and I'm ignorant of other rect…

Yes, absolutely! The Mercator projection isn't the only conformal projection, but it is the only one for which north-south maps to the vertical axis, and east-west to the horizontal axis. That means that it maps the whole world onto a rectangle, which works well both for computers and interior decorating.

As for other rectangular projections, the most common is the equirectangular (or plate carrée), which simply maps (longitude, latitude) to (x, y). This is a pretty common representation for gridded global data.

Re: Printing a wall-sized world map and what I've learned from it

#65

Post by pricechild »

UnoriginalGuy wrote: post #30
dietrichepp wrote: post #7

This guy "loves world maps" but chose Mercator for the wall of his room? I guess there's no accounting for taste. There are hundreds of projections to choose from, why choose the one optimized for navigation by compass ?

He only had a Mercator map source data. Unless you know how to switch Google Maps into Peters Projection mode? I am surprised people who read the article are even asking this considering how much he struggled even to get the source image (and how he ultimately wound up manually stitching together print screens).

Incase anyone really does want to do this: http://www.gdal.org/gdalwarp.html is awesome.

Re: Printing a wall-sized world map and what I've learned from it

#67

Post by ChrisArchitect »

a long time ago, like, in the early years of google maps, I used some perl code someone published to pull down the tiles necessary to print off a 16 page map that I could tape together and put on the wall. I think the code was taken down shortly after because of a legal claim. Google obviously doesn't want their service/tiles being used for that....data/imagery owned by them and whatever map data company... Whether you can easily download the tiles or not due to browser caching, doesn't make it legal to use in stuff.

But all in all, hats off, fun project/good results

Re: Printing a wall-sized world map and what I've learned from it

#68

Post by germanier »

ChrisArchitect wrote: post #67

a long time ago, like, in the early years of google maps, I used some perl code someone published to pull down the tiles necessary to print off a 16 page map that I could tape together and put on the wall. I think the code was taken down shortly after because of a legal claim. Google obviously doesn't want their service/tiles being used for that....data/imagery owned by them and whatever map data company... Whether y…

Well, the poster is in Germany, so German laws apply and section 53 of the copyright law (which is referred to in the post) clearly states that this is allowed use:

> It shall be permissible for a natural person to make single copies of a work for private use on any medium, insofar as they neither directly nor indirectly serve commercial purposes, as long as no obviously unlawfully-produced model or a model which has been unlawfully made available to the public is used for copying. A person authorised to make copies may also cause such copies to be made by another person if no payment is received therefore, or if it involves copies on paper or a similar medium which have been effected by the use of any kind of photomechanical technique or by some other process having similar effects.

http://www.gesetze-im-internet.de/englisch_urhg/englisch_urh...

Re: Printing a wall-sized world map and what I've learned from it

#69

Post by fennecfoxen »

HCIdivision17 wrote: post #57
coldpie wrote: post #33

Earlier quoted context omitted.

Hammer retroazimuthal, back hemisphere. Which is, coincidentally, also my favorite skateboarding move.

This is really cool looking, and I have no idea what you'd use it for. And this is just the neatest thing to play with: https://www.jasondavies.com/maps/hammer-retroazimuthal/

"As a retroazimuthal projection, azimuths (directions) are correct from any point to the designated center point." (-- Wikipedia, which knows everything and is never wrong.)

It looks like one retroazimuthal variant (the Craig retroazimuthal) is sometimes called the "Mecca projection", so you know which way to kneel at sundown if you're into that sort of thing.

Re: Printing a wall-sized world map and what I've learned from it

#70

Post by unreal37 »

lostfocus wrote: post #48
iak8god wrote: post #45

Earlier quoted context omitted.

Ugh, that was my first thought when I got to the end too. After all that work and expense, I was hoping he'd installed a ferromagnetic backing and was going to use tiny magnets as markers.

Well, once he killed it with his pins, he can print a new one with a different projection.

Yes, the printing was the easy part. In a few years, when the ink fades, he can print it again and remount on the same surface.
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