In a previous post, we shared ideas about key elements that make great maps according to our friends atMap the Xperience. They presented awebinar on the subject, so we poached their ideas forPart 1 of this blog discussing the importance of map quality and connecting with the user. In Part 2 we’ll expand on the other two elements, Presentation & Design, and Accuracy.
After identifying the target audience and deciding on the level of detail required, putting all of the relevant data on a map while keeping it readable is a challenge. Good maps document what the reader needs to know at a basic level to prevent getting lost. Great maps highlights what the reader needs to know to fully experience the mapped area. It all starts with map accuracy and the readability imparted by the presentation and design of the information.
Presentation & Design
A map quickly becomes cluttered as additional layers of data are added so how do you present all of that in a way that doesn’t make people’s eye’s pop out? It pays to have some knowledge of design, or get some advice from someone who does. Can you use colour to convey any of the information on the map, and is the colour scheme pleasing to look at? Do the symbols make sense to anyone but you? Are they simple and not open to interpretation? Can shading or patterns be used to highlight map features? Map The Xperience takes the design process very seriously and highlights their 3D hillshading asone of the features that make their maps unique.
An equally important part of the discussion about presentation includes thinking about how and where readers will use the map. Is it in paper format or digital? Will they be reading it thousands of feet in the air in a hot air balloon, at a table studying the map with a group, or on a tablet in the middle of a forest? Anticipating how a map will be used helps to make design decisions such font and symbol sizes, label placement, and the use of legends.
Accuracy
What’s the point of a map that isn’t accurate? This is obvious and yet still worth mentioning. While lots of lovely art is made by taking liberties with the accuracy of map elements (that’s another blog post) maps for specific activities need to be accurate – spatially and in the supporting information. This can mean field testing maps in the way thatMapsynergy tests its ski resort maps by actually skiing the hills, andNew York-New Jersey Trail Conference constantly updates maps according to data collected by its members and staff. It can also mean augmenting physical data with local knowledge.Rhonda Lerner visits each of the businesses listed on her tourist map to verify that the the are tourist-friendly and current.Pixmap Cartografia Digital researches the local names for locations on their maps of Argentina and Chile, because in the end, who can knows a place better than the people who live there.
In summary, good maps are functional while great maps add to the experience of visiting a place by being, all at once, informative, accurate, easy-to-use and pretty to look at. It’s no easy feat to meet all of those criteria. Perhaps the pursuit of the perfect map is the reason why cartographers are so passionate and dedicated to their craft.
The Channel Management tool in Geographic Imager is excellent for quickly making false-color composites from multispectral images in Adobe Photoshop. In this blog, we’ll take a look at Channel Management and see how it can be used on LandSat 8 imagery.
Most satellite providers supply a tile or scene as several images while each image captures a different wavelength of the satellite’s electromagnetic spectrum. The LandSat 8 satellite instruments measure in the visible, near-infrared and shortwave infrared portions of the spectrum. Its images have 15-metre panchromatic and 30-metre multi-spectral spatial resolutions. Here is a list of all LandSat 8 band names, bandwidth, and resolution.
Band # | Type Bandwidth (µm) | Resolution (m)
Band 1 Coastal Aerosol | 0.43 – 0.45 | 30
Band 2 Blue | 0.45 – 0.51 | 30
Band 3 Green | 0.53 – 0.59 | 30
Band 4 Red | 0.63 – 0.67 | 30
Band 5 Near Infrared (NIR) | 0.85 – 0.88 | 30
Band 6 SWIR 1 | 1.57 – 1.65 | 30
Band 7 SWIR 2 | 2.11 – 2.29 | 30
Band 8 Pan | 0.50 – 0.68 | 15
Band 9 Cirrus | 1.36 – 1.38 | 30
Band 10 TIRS 1 | 10.6 – 11.19 | 30 (100)
Band 11 TIRS 2 | 11.5 – 12.51 | 30 (100)
Before starting, you can download some sample LandSat 8 imagery here and follow this tutorial.
To create different band combinations, we’ll first need to combine images into one image and then use Channel Management to assign band combinations.
1. In Adobe Photoshop, open all of the 30-metre resolution images:
Band 1 – Coastal Aerosol
Band 2 – Blue
Band 3 – Green
Band 4 – Red
Band 5 – Near Infrared (NIR)
Band 6 – SWIR 1
Band 7 – SWIR 2
Band 9 – Cirrus
When using Landsat 8 imagery, file names have a _B and the band number as a suffix (e.g. LC80450292013225LGN00_B1.TIF). Note that Band 8 wsa not used because it is has a different resolution.
Now that the band images are open, we can continue to combine the images into a single image using the Adobe Photoshop Merge Channels feature to store the spectral information. Each channel is grayscale which can be used to store different information.
2. Go to View > Channels to open the Channels panel. In the panel options menu, select Merge Channels. In the Merge Channels dialog box, the Mode will automatically default to Multichannel because there are eight channels. Click OK.
The Merge Multichannel dialog box will immediately appear. In this dialog box, we’ll specify each image to use for each channel. It’s very important to assign a channel to the according image. In this case, the naming convention of the images makes it easy because the images are in the correct order. In addition, when combining multiple images, it is good practice to ensure that all the images have the exact same image size and are georeferenced the same.
3. Notice the “Specify Channel 1” text, you’ll assign the Band 1 image to it. Click the Image drop-down to display all the images that are compatible to be merged. Select the first image which ends in _B1.tif and click the Next button. For “Specify Channel 2”, select the image ending with _B2.tif and click Next.
4. Repeat the steps for the remaining images until all eight channels have been assigned an image, ensuring the channel number matches the image band number. The only exception will be Channel 8 which uses Band 9 – Cirrus (_B9.tif) because we didn’t include the panchromatic band 8 which has a higher resolution and different georeference.
The images are now merged into a single image in Multichannel mode. Since an image in Multichannel mode is not compatible with Geographic Imager, it will have to be converted to Grayscale mode.
5. Go to Image > Mode > Grayscale. This will assign the first alpha channel (Band 1 – Coastal Aerosol) to use the Grayscale colour space.
6. In the Channels panel, rename all the channels to their corresponding bands.
Alpha 2 -> Band 2 – Blue
Alpha 3 -> Band 3 – Green
Alpha 4 -> Band 4 – Red
Alpha 5 -> Band 5 – NIR
Alpha 6 -> Band 6 – SWIR 1
Alpha 7 -> Band 7 – SWIR 2
Alpha 8 -> Band 9 – Cirrus
Renaming channels makes assigning band combinations easier in later steps. It is recommended to save this image as the source for all band combinations and use Save As to create a new images when saving band combinations.
7. In the Geographic Imager panel, click the Channel Management button.
The Channel Management dialog box shows the current colour mode is Grayscale.
8. Change the Color Mode to RGB Color.
Now the fun begins, we can easily create any band combination. A traditional color infrared image (CIR) is band combination 5-4-3. This refers to what band is assigned to the RGB channels, respectively. CIR is good at determining the health of vegetation; the cell structure of leaves strongly reflects near-infrared light and the stronger the light sensed, the healthier the plants are.
8. Assign Band 5 as the Red channel, Band 4 as the Green channel, and Band 3 as the Blue channel.
9. Click OK to complete the process.
We now have a image which can be used to determine healthy vegetation which is shown in bright red. This makes it easier to determine different types of vegetation making it easier to identify crops and wetland.
Some other common Landsat band combinations are:
Natural Color: 4-3-2
False Color (urban): 7-6-4
Color Infrared (vegetation): 5-4-3
Agriculture: 6-5-2
Atmospheric Penetration: 7-6-5
Healthy Vegetation: 5-6-2
Land/Water: 5-6-4
Natural With Atmospheric Removal: 7-5-3
Shortwave Infrared: 7-5-4
Vegetation Analysis: 6-5-4
Another band combination of 6-5-2 can show how healthy vegetation is.
10. Use the History panel to go to the previous step.
This will reset the Channels so that another band combination can be configured easily.
Another great way to make non-destructive edits is to use Adobe Photoshop adjustment layers. Adjustment layers layer can be used individually or in combination to adjust settings such as levels, exposure, contrast, brightness, hue, and saturation to make it easier for the human eye to identify features. It is not recommended to alter an images resolution if it is going to be used in third-party remote sensing software.
There are several options when saving an image like this and it depends on whether you want to maintain the channels or not. When the channels aren’t needed, GeoTIFF is a popular format and is compatible with most spatial software applications. In the TIFF save options, you can uncheck the option for Alpha Channel and Spot, which will prevent saving the alpha channels and will create a saved copy. You can also simply save it as a PSD file (a default reference file will be created) and with all the alpha channels intact. Note that including channels will increase the size of the file.
June 18th is #InternationalSushiDay, and as they say “You can’t buy happiness, but you can buy sushi, which is kind of the same thing.” Sushi has become so mainstream that you can find a sushi restaurant almost anywhere. With the wide variety of ingredients and flavours available in maki rolls, sashimi and sushi, no wonder it’s such a popular meal. To celebrate, we made a map! Instead of focusing on Toronto this time, we went to the west coast to highlight some restaurants in Vancouver that have ‘Bucket List’ sushi. These restaurants were chosen from this Narcity article. While not all of them are featured on the map, the 12 restaurants shown are still serving bucket list sushi items! If you try any of these, please leave a comment! Interested in how we made our sushi map? Keep reading!
The City of Vancouver has a great open data portal, which is where we pulled the part of our data.
We got our street and park files from the portal, and created the sushi points using the MAP Point Plotter (one of my favourite tools!). Using the restaurant addresses provided in the article, we plotted each of the points on the map.
Once all of our points were in, we used a MAP Theme to style the streets. Ours looked like this:
Once the streets were styled, and colours were chosen it was time to style the rest of the map. We put a land mass file in to give boundaries, and show the coast line.
We styled the restaurants with different pieces of sushi, and included their addresses for easy reading. But, the most important feature and point of this map, were the bucket list sushi items that each of these restaurants serve. To show those featured menu items, we added them to the MAP Attributes (and included their Yelp rating, along with a photo of food from their restaurant).
Once those were in, we used the MAP Web Author tool to make the map interactive! When you view the map and click on the sushi icon for each of the restaurants, you’ll see the restaurant name, the bucket list sushi item, the Yelp rating, and a picture of their food. Here’s what our Web Tags look like.
Here’s what the final map looks like! If you click on the sushi pieces, you’ll see the tags we created in MAP Web Author. Interested in the PDF? It’s also linked below. We’ve put the Adobe Illustrator file up as well, if you’d like to take a look or play with the map itself! Happy #InternationalSushiDay!
The field of cartography is filled with jargon and terminology that can pose a challenge for newcomers learning to use mapping software such as MAPublisher to make beautiful maps, and those who don’t have a formal background in cartography. It also doesn’t make it easier when different software packages have their own variations on certain terms. To help the cause, we have compiled a short list of common cartography terms or “carto-jargon” that you may encounter while using MAPublisher or Geographic Imager.
Basemap
A basemap is a background image which can include aerial imagery, topography, terrain and streets and other fundamental layers and is used as a starting point to create a new map. The basemap is georeferenced and is usually the most accurate source of spatial information within the data system that makes up the finished map. Additional layers of data such as labels, symbols and paths are then added to the basemap to create the final product.
Feature
Any real-world object that is represented on a map is a feature. Features can encompass large areas of a map, such as bodies of water and mountain ranges, or they can be discreet objects like parking areas, public washrooms or fire hydrants.
Attribute
Attribute data is information about spatial features and is stored in tables. It is also the information that specifies the appearance and labeling of features on a map. For example, the graphic attributes of a river might include the thickness of the line, line length, color, and the name used for labeling.
Control Point
A control point is a location on the map with known pixel (x,y) coordinates. Control points are used in georeferencing to allow for extrapolation of the relative location of other points whose exact coordinates may not be known.
Coordinate System
A coordinate system is a reference system used to represent the locations of geographic features on a map. It provides the basis for identifying locations on the earth’s surface. There are thousands of different coordinate systems, most of which are limited in use to highly specialized purposes.
Projection
The earth is not flat and so imagining that it is for the purpose of putting it on a 2-dimensional map results in some distortion. A projection is a method by which the curved surface of the earth is portrayed on a flat surface and is based on a mathematical transformation of the earth’s lines of longitude and latitude onto a plane. There are many different projections, each of which distorts distance, area, shape, and direction is some way, therefore no projection can result in a perfectly accurate flat map. Check out theAvenza Projections Guide for a more detailed information.
Georeferencing
Georeferencing involves aligning geographic data to a known coordinate system so it can be viewed, queried, and analyzed relative to other geographic data on the same map. Georeferencing may involve shifting, rotating, scaling, skewing, and in some cases warping, rubber sheeting, or orthorectifying the data to improve accuracy.
Graticules and grids
Graticules are the network of longitude and latitude lines on a map or chart that relates points on a map to their true locations on the earth. You can think of this a grid system – in fact, the terms are sometimes used interchangeably, but there is a subtle difference. Graticules are derived from 3-dimensional ellipsoidal shape of the earth and are formed by the the lines of latitude (parallel lines circling the earth), and lines of longitude (non-parallel lines converging at the earth’s poles). A grid system is comprised of a set of parallel and perpendicular lines that are superimposed on a flat projection of the earth, creating an x,y coordinate system. An example of a grid system is the Universal Transverse Mercator (UTM) system.
Themes
In MAPublisher, MAP Themes are a collection of thematic cartography tools designed to automate how styles and symbols are applied, charts are produced, and data is plotted. There are three themes which you can be customized to suit your needs: Stylesheet, Chart, and Dot Density. MAP Themes offer a lot of flexibility as they can be edited, applied, duplicated, automated, exported, and cleared without affecting the spatial referencing of map features.
This is just a small sampling of the more robust glossary of terms available in the ourMAPublisher andGeographic Imager documentation packages.
MAPublisher has been simplifying the process of making maps beautiful for cartographers for more than 20 years. We are always adding new features and improving others, some of which have impacted the overall workflow and affect a majority of users. Other are more ‘niche’ in their application and the functions they perform. Here are a few favourite features that you may, or may not be aware of, as identified by the people who helped design and build them.
MAP Tagger ToolMichael L. – Product Marketing
I like the MAP Tagger Tool because it’s incredibly fast to create labels by clicking features on the artboard. Labels are created using attribute data as a source for the labels. In dense areas, the Map Tagger has flexibility to style and attach leader lines according to placement rules.
MAP Web AuthorWill H. – Sales
The MAPublisher users I speak with are usually impressed with Web Author and are surprised that it is included in the MAPublisher package. MAP Web Author lets Adobe Illustrator documents with GIS attributes be exported to interactive HTML5 web maps complete with callouts, rollovers, layer control, search, pan and zoom controls. With a little bit of knowledge of CSS (Cascading Style Sheets) and JavaScript you can embed interactive maps into any web page. The map below was created by the National Park Service.
Scale and Rotate by AttributeAndrew P. – Software Architect
We added this for a customer who had an interesting use case involving a pattern fill for lava flow. The map broke down an area into sub-areas by lava flow (direction, intensity, etc.). He wanted a way to use the attribute data he had in his map to automatically do a bunch of things he would otherwise have to do by hand, very carefully. In particular, he used the feature’s ability to rotate the pattern of area to match the lava flow direction, which sounded very cool (no pun intended) to us!
MAP Locations ToolMichael L. – Product Marketing
Most users don’t know what MAP Locations does (allows you to define real world coordinates for a location in a document) and how it’s actually useful. It sounds complicated, but it’s actually simple and far reaching throughout the product. MAP Locations can be used in several MAPublisher tools as references for georeferencing, for corners, for locations to draw lines, and locations to plot points. They can also be used to identify map and page anchors.
Add Calculated DataAndrew P. – Software Architect
Add Calculated Data is essentially a tool to update or add attribute data, but it allows users to feed in things that a user would find difficult to calculate themselves such as centroids, north angles, and art bounds. It also lets you pull in and store data like stroke or fill colours, in case you need to export them to a format that doesn’t support colours natively. You can even have it pull in elevation data!
For the majority of Avenza Maps users, layers are indispensable. Not only are layers a repository where placemarks, tracks, and photos are stored, but they also enable you to both manage and share map feature data.
With the release of Avenza Maps 3.5, Android users will be introduced to a feature that was previously only available on the iOS platform, the Layers tab. The Layers tab is an invaluable resource which provides a complete listing of all layers in the app database, including their existing map associations. But what is most exciting about the Layers tab is it’s new ability to export layers. Exporting layers from the Layers tab will streamline data archiving. From the Layers tab, you now have the ability to export an individual layer, multiple, or all existing layers in one fell swoop.
Let’s see just how easy it is now to archive your map feature data.
Say we had two topographic maps. One map contains two layers while the other has three separate layers. Below is an example of how all five layers can be exported from the Layers tab at once.
iOS
Android
If you plan on importing your exported data back into the app, it is important that you export to either the KML or Shapefile (requires a Pro subscription) formats. Once you have tapped on Export, navigate to the storage location and tap Upload (iOS) or tap the check-mark icon (Android) to export. All of your layers will be exported to a single file for archiving. If you wish to restore these layers at a later date, you can simply import them back into the Layers tab and all layers will appear in the layers tab as they did prior to export.
The following example is very similar but this time we are only exporting a selection of layers from the Layers tab.
iOS
Android
When it comes to exporting map feature data from multiple maps, the Layers tab is now clearly the most efficient method. A word of caution, if you are exporting large amounts of map feature data, it is advised that you break your export up into separate files as opposed to saving all of your layers to a single file. If you are exporting to email, there are restrictions to the size allowed for file attachments. Additionally, when exporting large files, there are resource limitations that may come into play and which vary by device and work environment.
Your data is a valuable resource. Countless hours can be devoted to data collection and the resulting map features are vital to the completion of your work projects. For most, it is extremely important to regularly export data for backup or archiving. Exporting layers from the Layers tab has just made this process that much easier.
Recently we hosted a webinar with our friends at Map the Xperience who shared their thoughts on some of the key elements of cartography and making maps from good to great. Part One of this blog discusses two of the four elements in greater detail: Map quality and connecting with the user.
Good maps are ones that the reader can use to get from A to B with as few unwanted detours as possible. However, a great map can go well beyond the functional while helping users enhance the experience of the map area. It all starts with readability and the ability to meet the needs of map users who may want to use the same map in different ways, for different purposes.
1. Map Quality
Map quality encompasses several different aspects of map publishing including resolution and depth of detail. Accuracy is another element of quality which we will cover in a future Part Two of the blog, but let’s start with resolution. Publishers have always been careful with printing maps at a resolution that supports the size of the printed map, whether the finished map will appear in a book or on a wall. The challenge is that today, maps may be printed in a variety of formats, and used in a variety of ways and therefore have different requirements for resolution. Print on demand services like MapSherpa offers a wide range of printed sizes, and the ability to isolate a portion of a particular map for printing. To make it work, maps must be high enough in resolution to print well in larger formats.
Print sizes are not the only challenge facing map publishers today. Maps printed on alternative media are becoming more popular. Map the Xperience also prints maps on blankets and clothes as keepsake items and recognizes the special requirements for resolution in order to maintain the integrity of the map on different media. Furthermore, digital maps and maps for web applications need to be created in high-resolution to support the ability to zoom in and out to various map scales.
The important message here is that great maps are made at the highest and most appropriate resolution possible to support all of the map formats, print sizes, and media types in which it will be published or displayed.
2. Connecting With the User
Just like with any manufactured product, the more you know about your target audience, the better you can be at producing something that they will love. Maps are no different because if you can anticipate what the end-user wants and needs to know, and incorporate them into the map, users will appreciate and value it. We are big fans of activity-specific maps which tend to be some of the most popular ones in the Avenza Map Store. That’s because maps that are made for a particular activity or intended for a set of activities in mind tend to have the most relevant detail and useful features for the intended map readers. Publishers like MapSynergy understand the importance of connecting with users in this way, producing maps of popular ski resorts that show far more information than the average resort map, including direction of runs, boundaries, and even the location of trees. Creating maps enriched with audience-specific information is much easier today than it used to be with better data sources, imagery, and mapping software that simplifies working with layers of data.
Connecting with users also takes into account the role that maps can play in helping the user to plan a trip, experience everything the area has to offer, and to remember the trip once they have returned home. Many people find maps to be fascinating to look at, but think about how much more interesting it is to look at the map of an area you’ve traveled, remembering the things you saw and did. Map the Xperience makes maps for hunting and fishing and they take great care to include everything from boat put-ins and take outs, land designations, campgrounds and other features useful to hunters and anglers.
Great maps illustrate exactly what the user needs and wants to see. They go well beyond being functional to being scalable to any format, and connecting with the user in such a way as to enhance the user’s experience before, during and after the trip. Stay tuned for Part Two of this blog post where we discuss two more elements of great maps—Accuracy and Presentation.
We’re excited to announce that we’ve completed the release of Avenza Maps 3.5 for iOS and Android. This update contains new features and performance improvements as well as fixes for reported issues. Some highlights are mentioned below, for the full release notes see below.
Plus subscription. We’ve renamed the Unlock Map Imports subscription tier to Plus. The simply named Plus subscription tier will better align with more features that we’ll be introducing in the near future. This subscription still allows you to import as many of your own maps as you want—ideal for map and outdoor enthusiasts who enjoying sourcing and loading their own or third-party maps.
Active and inactive maps. In this release we’re introducing the ability to make imported maps (not including those downloaded from the Map Store) inactive. In previous releases, the standard version (without a paid subscription) allowed you to only import up to three of your own maps into the app and were limited from importing any more. However, now you’ll be able to import as many of your own maps as you’d like. The first three imported maps will be considered ‘active’ and available to use with all of the app’s functionality. Subsequent imported maps will be considered ‘inactive’. Inactive maps can still be opened and viewed, but without GPS location and map tools enabled. You will have the ability to delete active maps that you no longer use and then activate new ones to stay within the three active map limit. Maps downloaded from the Map Store (versus imported from an external source) are always location-enabled and are never limited. To import an unlimited number of your own maps with full location-enabled features and functionality, Plus and Pro subscriptions are available.
Sort and filter your maps. This release provides some handy sort and filter options on the My Maps screen. You’ll have the ability to sort by distance (how far away a map is from your current location), by name, by date, and by how much storage the map takes (measured in MB). In addition, you’ll now be able to filter maps to show only those from the Map Store, maps that you imported, folders and collections, active or inactive maps, just maps (no folders), or all items.
Map Store Login and My Account improvements. The user interface around logging and viewing your Avenza Maps account details has been vastly improved. You now have the ability to change your password, change your email, and view your download history. The Download History screen has new functionality as well. Previously you were only able to download one map at a time. Now you’ll be able to select multiple maps at a time and download in bulk. In addition, you’ll also be able to access map descriptions without having to go to the Map Store to look it up.
Layers now available on Avenza Maps for Android. Rejoice Android users, layers are finally here! Having the same functionality as the iOS version, map features (placemarks, lines, tracks, areas, photos, and schema) are now contained on layers. Map features can be managed here, including adding, deleting, and editing map feature information. In addition, the layers can be linked (and unlinked) to maps, so that map data can continue to be used even if a map is no longer on the device. Similarly, if that map is installed again, you’ll be able to link that layer to the map again. You’ll also be able to export layers data directly from the Layers screen without having to go into each map.
Better quality Map Store previews. All of the map listing previews in the Map Store have been updated and now have higher resolution of busy sections of the map to provide better detail of features, lines, labels, and colours.
Release Notes
User experience improvements, including sorting and filter options on the My Maps screen
Newly designed Map Store Login and My Account screens
Re-discover, select and re-download previously purchased Map Store maps using new options available on the Downloads History screen
Export Layers data directly from the Layers screen
Link a layer to any available maps or unlink from all maps from the Edit Layer screen
Better quality map previews in Map Store
More granular control of map features’ visibility
Manage, import or export your data independently of maps using the new Layers tab on Android
You would be hard-pressed to find a person living in a developed country who has never used Google Maps, let alone heard of it. In May 2017, Google announced there were over two billion active Android devices and that the Google Maps app had over one billion downloads. Take into account the fact that Google is the runaway leader among search engines, it’s not a stretch to think that Google Maps is one of the most widely utilized desktop and mobile applications in the world.
While Google Maps has been in use since its debut in 2005, few have taken the time to consider the technical cartographic elements under the hood. For most everyday users, they don’t need or care to understand the cartography—it’s a tool to get directions, view their neighbourhood, or scope out a destination for their upcoming trip. However, cartographers and GIS software developers alike have been reluctant to praise Google. This is because Google Maps uses a variant of the well-known Mercator projection known as Web Mercator (also often referred to as Pseudo Mercator or Google Web Mercator).
While there are several pros and cons of the Web Mercator projection, it comes under fire mainly due to the fact that locations away from the equator undergo severe stretching and distortion. This can be easily visualized using thetruesizeof.com, which is a tool that allows users to compare the size of countries if they were located at the same latitude. Let’s use Brazil and Greenland as an example. In their normal locations, Greenland appears to be almost four times the size of Brazil.
However if we move Greenland down to the equator, it shrinks to nearly a quarter of the size of Brazil, which in reality it is.
A number of publications, presentations and GIS blogs have warned about the “dangers” of mapping using Web Mercator. A lack of understanding between the standard Mercator and Web Mercator projections and the resulting inaccuracies forced the National Geospatial-Intelligence Agency (NGA) to issue an advisory to all internal departments prohibiting the use of Web Mercator. But the popularity of Google Maps has prevented Web Mercator from going away, thus GIS software and third-party mapping applications continue to support it.
In previous versions of MAPublisher (9.9 and earlier), the absolute scale (e.g. 1:500,000), relative scale (i.e. 1 in = 1 mi), and scale bar length were all calculated based on the projection’s point of true scale. Because Web Mercator’s point of true scale is always along the equator, the scale bar tool did not account for the stretching a map experiences as latitude changes. The scale values conflicted with the actual distance on the Earth.
We received numerous feature requests to have the scale bar length calculated based on the latitude at the centre of the MAP View. For MAPublisher 10.0, we made adjustments to our scale calculations to do just that. However, we quickly realized we were still reporting the equatorial absolute scale value.
To fix the discrepancy between the two values, MAPublisher 10.1 introduced an option to adjust the absolute scale value by the scale factor, which is calculated based on the MAP View’s centre latitude. This ensures all three scales are in agreement. It should be noted that this feature is best suited for medium to large scale maps. Small scale maps cover too great a distance for the scale to be consistent across all areas.
So let’s recap. Google Maps is great for the beginner and amateur cartographers, providing an easy to use tool for spatial data visualization. However, the Web Mercator projection should be avoided, especially if performing data analysis or if mapping for military, surveying, or geodesy purposes. But what happens when you absolutely need a Google-friendly web map? Do not include the absolute or relative scale values because as the zoom level or location changes, the scale value is no longer correct (in some cases a scale bar is okay). Additionally, Google and Bing web tiles display dynamic scale bars that update based on map location and zoom level. However if you really want to include a scale graphic to give the reader some perspective, MAPublisher provides the tools necessary to ensure your map is as accurate as possible.
Whether you’re an experienced atlas maker or embarking on your first project, we all know producing an atlas is no small task. In short, an atlas consists of a series of maps and an associated index. Seeing that cartographic content often takes centre-stage, when planning your project it is easy to assume that the map-making process will be the most demanding. However, the proper indexing of map features is often by far the largest individual task when it comes to producing an atlas and can be quite burdensome.
You will be happy to know that MAPublisher 10.1 makes indexing that much easier with the addition of the Include Page Numbers option to the Make Index tool. This advanced option completely automates the indexing of page numbers while also enabling the indexing of two page maps on a single artboard.
For atlas makers, this new addition will streamline and improve the indexing process making it a key enhancement considering the primary function of an atlas index is to help the user locate features and points of interest on map pages.
Let’s take a look at a basic street atlas of Cochrane that was created using MAPublisher 10.1. Cochrane is a town located in Northern Ontario which is not only famous for its mascot Chimo but also for being the hometown of Tim Horton, founder of Canada’s largest coffee chain.
The atlas is divided into four sections: grid cells A1, A2, B1, and B2. Each cell contains two separate map pages numbered two through nine.
The following is a simple example which demonstrates the page indexing for atlas pages eight and nine found in grid cell B2.
Atlas makers can now index their page numbers as easy as one-two-three!
Step 1
To start, using the MAPublisher Grids & Graticules tool, generate an Index Grid with one column and one row (1×1). Although the Index Grid option was selected, the Graticules or Measured Grid options can also be used if it better suits your atlas design needs. Additionally, Cell Reference Labelling was enabled and the advanced labelling options were set as displayed.
Step 2
With your Index Grid created, access the Make Index tool which will initiate the map indexing process. Since we’re indexing streets in this example, we’ll go with the Make index based on feature position and attribute value. The feature position will be relative to which page or pages the street falls on while the attribute value will reflect the street’s name. In this example, streets which span two atlas pages have been highlighted with a yellow background on the map.
Step 3
Since a single artboard is being used to map features which span two atlas pages, the Advanced option Include Page Numbers will be enabled with a horizontal page layout dividing the artboard into page 8 and page 9.
Simply click OK twice and your atlas pages will be indexed with the results written to a delimited text file as displayed below. From here, this file can be formatted and refined within a software like Microsoft Excel, Google Sheets, Quark Xpress, etc.
Portion of the delimited text file output:
Same portion imported into Microsoft Excel:
Note: streets which span two pages have been highlighted to correspond to the map example.
By necessity, indexes are created towards the end of each project when atlas delivery deadlines are looming. It is therefore very important that the technology and methods used be robust and efficient. The introduction of the Include Page Numbers option has enhanced and simplified the map indexing process while meeting the specialized needs of atlas cartographers.
