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Home Maps Which is the best map projection? Robinson American geographer and cartographer Arthur H. Pros: Shows the entire world at once Cons: Compromises both area and angles, especially at the poles Interesting: Which map did Christopher Columbus use? Pros: Reasonably accurate shapes and sizes of countries Cons: Land masses closer to the poles still enlarged Must see: These 5 tools will let you master map projections AuthaGraph This is hands-down the most accurate map projection in existence.
Let us know in the comments below! Nice rundown. Pleased to see you included Authagraph was included. That would be my pick. Michael Ossipoff. My favorite is the Mollweide, because the distortion makes it look 3d. Why did you ignore the homolosine projection? Please enter your comment! In the first concept of this topic, you'll look at this issue in more detail.
Second, a good projection minimizes distortion in your area of interest. This issue is complicated for instance, are all types of distortion equally important? But the second and third concepts in this topic will present some fairly simple and useful rules. Most of the time, it's not that hard to pick a good projection. Apart from what you'll learn in the rest of the topic, here are a few points to keep in mind:. ArcMap has a large number of predefined projections organized by world, continent, and country.
You can navigate quickly to appropriate projections for any part of the world. When you're working at large scales—for example, provinces or districts within countries—distortion doesn't play a significant role, and almost any projection that is centered on your area of interest is okay.
To put it more picturesquely, you can't flatten a beachball without a lot of distortion, but you can flatten a postage stamp on a beachball. It's easy to change projections and to modify projection parameters in ArcMap.
So it's almost never too late to correct a flawed choice. You may be working on a project or for an organization where the question of which map projection to use has already been decided. For example, the State Plane and UTM coordinate systems are established standards for many large and medium-scale maps of U.
You'll learn about these coordinate systems and the projections they are based on in the next module. What is the map's purpose? When you choose a projection, the first thing to consider is the purpose of your map. For general reference and atlas maps, you usually want to balance shape and area distortion. If your map has a specific purpose, you may need to preserve a certain spatial property—most commonly shape or area—to achieve that purpose. Maps that preserve shape On a conformal projection, all local angles measured from a point are correct and all local shapes are true.
You should use a conformal projection when the map's main purpose involves measuring angles, showing accurate local directions, or representing the shapes of features or contour lines.
This category includes:. Click each of the maps above to learn more about them and the projections they are in. Most of the maps in the list above would be large or medium-scale. In fact, most large-scale maps nowadays are conformal, regardless of their purpose. Why are most large-scale maps conformal?
At large scales, a conformal projection centered on the area of interest produces insignificant errors in distance and area. These errors are often smaller than what D. Maling, author of Coordinate Systems and Map Projections , calls the "zero dimension"—the point at which projection distortion is less than the error caused by physical properties of the map paper shrinkage, pen width, and so on. It may also apply to smaller scales if the area of interest has a compact shape.
For example, Maling says that the area distortion in a , Transverse Mercator projection of England is trivial. Maps that preserve area On an equal-area projection, the size of any area on the map is in true proportion to its size on the earth. You should use equal-area projections to show:.
Equal-area maps have also been used as world political maps to correct popular misconceptions about the relative sizes of countries. Dot density map of federally-owned and Indian land in the U.
Albers Equal-Area Conic projection. Why equal-area projections are essential for dot-density maps? Dot-density maps show the concentration of an attribute in an area. The map of world population density you looked at before shown again below uses one dot to represent every one million people.
If areas are not in true proportion, the map will give false impressions. Countries that draw larger than their true area scale will look less dense than they should. Countries that draw smaller than their true area scale will look too dense. The Eckert IV projection applied here is used by the National Geographic Atlas, 7th edition , for several of its world thematic maps.
Maps that preserve scale No map provides true-to-scale distances for any measurement you might make. The Azimuthal Equidistant projection preserves true scale from a single specified point on the projection to all other points on the map. Possible uses for this property include:. The Two-Point Equidistant projection preserves true scale from two specified points on the projection to all other points on the map. This projection could be used to determine the distance of a ship at sea from the start and end of a voyage.
An Azimuthal Equidistant projection centered on New Delhi. Scale from New Delhi to all points and likewise from all points to New Delhi is correct.
A Two-Point Equidistant projection. Scale is correct from both Sydney and San Francisco to all other points. Maps that preserve direction On any azimuthal projection, all azimuths, or directions, are true from a single specified point to all other points on the map. On a conformal projection, directions are locally true, but are distorted with distance. Direction is not typically preserved for its own sake, but in conjunction with another property.
In navigation and route planning, however, direction matters for its own sake. The Gnomonic projection is unique among azimuthals in that every straight line drawn on it represents the arc of a great circle. Since a great circle is the shortest distance between two points, Gnomonic projections are useful for planning air and sea routes and for mapping phenomena, like radio waves, that follow shortest-distance paths.
A Gnomonic projection. Every straight line on the map is the shortest distance between two points. Plus you'll be able to see this from the map itself, rather than a business's page.
Apple Maps has a lot of that information thanks to partnerships with third party services like Yelp, Foursquare, and TripAdvisor, but not as much as Google Maps does. Encrypted and anonymized, naturally.
Apple also offers a 'Curated Guides' option as part of iOS 15, which offers recommendations on places to go when you're in a specific city. These guides can be saved and update automatically, so you're always up to date. Alternatively you can choose to create your own personal guide to share with friends and family. Whereas Google's insistence on including as much as possible means things can feel a little cluttered at times.
Despite the potential for information overload, Google still comes out on top in this instance. Apple Maps and Google Maps both have hands-free control, though they do work differently. Apple Maps is connected to Siri, which is installed on every iPhone by default. That means you can get everything set up right away, without any unnecessary extra steps. Siri does work with Google Maps now, but you have to specify where you want to send the command, otherwise Siri will default to Apple Maps.
Alternatively you can download and set-up Google Assistant, or toggle voice commands by tapping the microphone button on screen. Over on Android both Google Maps and Google Assistant are pre-installed, meaning you can set up hands-free commands right away. Accessing it is easy, and all you have to do is change the map type to the Street View option, and click an area highlighted in blue.
You then have the choice to either navigate in a split-screen mode that relies on you tapping locations on the map to get around, or by tapping and swiping within Street View itself. There's also the added advantage of Live View directions, which uses AR to overlay directions on what your phone can see - helping you navigate more effectively.
Live View is also set to get an upgrade in the near future, which adds business name and information to this mode. And that includes how busy they are at any given time, just in case there isn't a window you can peak though. However Live View relies on there being Street View coverage. Which is fine in a lot of public places, thanks to Street View's extensive coverage. But if you find yourself not covered, AR directions won't be available.
Accessing and navigating this mode is a little different too. You have to physically select a spot on the map and select the Look Around option first. It's pretty much identical to how Google Maps does it, if you're already familiar with Google's equivalent. So because of the sheer amount of coverage, and having a better selection of navigational choices, means Google comes out on top. However, Apple is fast catching up and Google Maps may not be in the top spot for long.
Apple has gone all in with privacy over the past few years, and Apple Maps is no exception. Plus none of the information that reaches an external server is associated with your Apple ID. That means you can go into the settings and delete it at any time, safe in the knowledge that it is gone for good. Because uploading that data to a server, no matter how secure, is riskier than keeping it on your device, you have to deliberately opt in first.
Google Maps does none of that. Google Maps does have an Incognito Mode, just like the Chrome browser, which limits the amount of data that is saved.
Discovering new places is easy on Google Maps, but only just.
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