Best tools for multimedia reporting Mon, 22 Aug 2016 14:48:32 +0000 en-US hourly 1 https://s0.wp.com/i/webclip.png 32 32 239681374 https://geojournalism.org/2014/06/tips-for-using-color-in-maps/ Mapbox Wed, 25 Jun 2014 19:31:02 +0000 Design Maps cartography color Easy map design https://geojournalism.oeco.org.br/?p=1031 <p>Color Theory and Mapping It&#8217;s important to realize how much your choice of color on a map can affect the story you are trying to tell with your data. As a brief introduction to some theories behind how to use colors on maps, here are three primary scheming designs for mapping data. Sequential Schemes Sequential [&#8230;]</p> <p>The post <a href="https://geojournalism.org/2014/06/tips-for-using-color-in-maps/">Tips for Using Color in Maps</a> appeared first on <a href="https://geojournalism.org">geojournalism.org</a>.</p> <h1 class="summary-item" id="color-theory-and-mapping" title="Link to this section"><a href="#color-theory-and-mapping">Color Theory and Mapping</a></h1> <p>It’s important to realize how much your choice of color on a map can affect the story you are trying to tell with your data. As a brief introduction to some theories behind how to use colors on maps, here are three primary scheming designs for mapping data.</p> <p id="sequential_schemes" title="Link to this section"><strong>Sequential Schemes</strong></p> <p>Sequential schemes order data from high to low, accenting the highest as a dark shade and the lowest as a light shade (or vice versa). Sequential schemes are best if you are mapping quantitative data and do not want to focus on one particular range within your data.<br/> <img alt="sequential" decoding="async" src="https://www.mapbox.com/tilemill/assets/pages/sequential.png"/></p> <p id="diverging_schemes" title="Link to this section"><strong>Diverging Schemes</strong></p> <p>Divergent schemes are best at highlighting a particular middle range of quantitative data. Pick two saturated contrasting colors for the extremes of the data, and the middle ranges blend into a lighter mix of the two. This is particularly great for accenting the mean of your data and exposing locations that significantly ‘diverge’ from the norm.<br/> <img alt="diverging" decoding="async" src="https://www.mapbox.com/tilemill/assets/pages/diverging.png"/></p> <p id="qualitative_schemes" title="Link to this section"><strong>Qualitative Schemes</strong></p> <p>If you are working with qualitative data, such as ethnicity or religion, you want to pick a series of ‘unrelated’ colors. The trick is to pick a really nice color theme so your map looks great. You can also accent particular aspects of your data by your choice of color. For example, one strong dark color among a group of lighter colors will ‘pop’ out of the map, highlighting that particular facet of your data against all others.<br/> <img alt="qualitative" decoding="async" src="https://www.mapbox.com/tilemill/assets/pages/qualitative.png"/></p> <h2 class="summary-item" id="sources-for-color-picking" title="Link to this section"><a href="#sources-for-color-picking">Sources for Color-Picking</a></h2> <p>Fortunately a number of sites are available to explore color themes. Below are links to some of these with a brief synopsis of their main features that will help you more easily navigate the seas of storytelling via aesthetics. The section ends with two reviews of purchasable tools that you can use from your desktop.</p> <h3 class="summary-item" id="0_255" title="Link to this section"><a href="#0_255">0_255</a></h3> <p>0_255 is a great site for picking between different shades of one color, so it’s ideal for sequential schemes. It gives you thirty options for any given color, allowing you to instantly copy the color’s hex code. There is a large grid of colors to select from for an initial color, and then 0_255 visualizes a range of shades based on that color. If the grid does not have the color you want, you can pick your own color by pasting in the hex code of your chosen color.<br/> <img alt="0_255" decoding="async" src="https://www.mapbox.com/tilemill/assets/pages/0_255_0.jpg"/></p> <h3 class="summary-item" id="color-scheme-designer" title="Link to this section"><a href="#color-scheme-designer">Color Scheme Designer</a></h3> <p>Color Scheme Designer allows you to select a color from a color wheel and presents several options for automatically generating colors complementary to your initial choice. Specifically, you can choose between:</p> <ul> <li>Complements</li> <li>Triads</li> <li>Tetrads</li> <li>Analogic</li> <li>Accented Analogic</li> </ul> <p>Once you’ve chosen your color and scheme, you’ll have a color table that gives you several variations of your colors and their corresponding hex codes.</p> <p><img alt="colorscheme" decoding="async" src="https://www.mapbox.com/tilemill/assets/pages/colorschemedesigner_1.jpg"/></p> <h3 class="summary-item" id="colour-lovers" title="Link to this section"><a href="#colour-lovers">Colour Lovers</a></h3> <p>Colour Lovers is great if you are looking for a design theme for mapping qualitative data. Active users contribute palettes to the site, and these palettes are searchable, browsable, and ready to be used on your project. Colour Lovers users also post patterns if you need some spatial inspiration as well.<br/> <img alt="colourlovers" decoding="async" src="https://www.mapbox.com/tilemill/assets/pages/colourlovers_0.jpg"/></p> <h3 class="summary-item" id="kuler" title="Link to this section"><a href="#kuler">Kuler</a></h3> <p>Kuler is a service similar to Colour Lovers offered by Adobe. A community of designers submit their own themes, which are available for RGB values and hex codes. The design of the site is a little less intuitive than Colour Lovers, but still worth checking out.<br/> <img alt="kuler" decoding="async" src="https://www.mapbox.com/tilemill/assets/pages/kuler_1.jpg"/></p> <p>There are a lot of great ideas being posted by an active community of contributing users. Kuler also provides extensive links to things like forums, help pages, as well as several articles on the importance of color and color theory.</p> <h3 class="summary-item" id="colorbrewer" title="Link to this section"><a href="#colorbrewer">Colorbrewer</a></h3> <p>Colorbrewer is great for contrasting the three kinds of color models mentioned in the first section of this article. It allows you to test out different color themes based on whether you want sequential, diverging, or qualitative schemes and to vary the number of color classes you want in your pallet (up to 12). It also provides some useful ‘further reading’ articles on these theories and other cartographic design ideas.<br/> <img alt="colorbrewer" decoding="async" src="https://www.mapbox.com/tilemill/assets/pages/colorbrewer.jpg"/></p> <h3 class="summary-item" id="pochade" title="Link to this section"><a href="#pochade">Pochade</a></h3> <p>Pochade is a color picking program that allows you to determine the RGB value and hex code of any color you see on your screen. It also provides a few different ways of manipulating your color, such as changing its HSB, RGB, or CMYK values. This program is available for download for $9.99.<br/> <img alt="pochade" decoding="async" src="https://www.mapbox.com/tilemill/assets/pages/pochade_0.jpg"/></p> <h3 class="summary-item" id="colorschemer-studio" title="Link to this section"><a href="#colorschemer-studio">ColorSchemer Studio</a></h3> <p>ColorSchemer Studio provides three main features: (1) a color class generator (up to 254 – many more than Color Brewer) based on two colors of your choice, (2) a ‘PhotoSchemer’, which allows you to upload a photo and determine up to ten different colors on your chosen photo and (3) integration with colourlovers, including a color browser and the ability to load colors into the first tool to manipulate on your own. ColorSchemer is a powerful tool for your desktop, available for the slightly higher price of $49.99.</p> <p>Originally posted on Mapbox: <a href="https://www.mapbox.com/tilemill/docs/guides/tips-for-color/" target="_blank">https://www.mapbox.<wbr/>com/tilemill/docs/guides/tips-<wbr/>for-color/</a></p> <meta content="text/html; charset=utf-8" http-equiv="Content-Type"/> <p>The post <a href="https://geojournalism.org/2014/06/tips-for-using-color-in-maps/">Tips for Using Color in Maps</a> appeared first on <a href="https://geojournalism.org">geojournalism.org</a>.</p> 1031 https://geojournalism.org/2013/08/how-to-map-photos-using-openstreetmap-and-tilemill/ Mikel Maron Wed, 14 Aug 2013 21:29:27 +0000 Maps cartography geotagging map design Open Street Map https://geojournalism.oeco.org.br/?p=268 <p>This guide takes four steps, demonstrating an overview of the whole flow and connection between four tools to build a photo map. This guide will hit the main points and highlight how the tools connect up with open data Introduction Recently, we organized a fun skill share with Map Kibera, and then again with Transparent [&#8230;]</p> <p>The post <a href="https://geojournalism.org/2013/08/how-to-map-photos-using-openstreetmap-and-tilemill/">How to Map Photos Using OpenStreetMap and TileMill</a> appeared first on <a href="https://geojournalism.org">geojournalism.org</a>.</p> <p>This guide takes four steps, demonstrating an overview of the whole flow and connection between four tools to build a photo map. This guide will hit the main points and highlight how the tools connect up with open data<span id="more-268"></span></p> <h2 class="summary-item" id="introduction"><a href="#introduction">Introduction</a></h2> <p>Recently, we organized a fun skill share with <a href="https://mapkibera.org/" rel="nofollow">Map Kibera</a>, and then again with <a href="https://www.transparentchennai.com/" rel="nofollow">Transparent Chennai</a>. The idea is to use OpenStreetMap and TileMill to create an interactive photo map. Here’s the <a href="https://a.tiles.mapbox.com/v3/groundtruth.map-vx5bbbu4/page.html" rel="nofollow">simple result</a> from working with Map Kibera.</p> <p><strong>Want to learn to create something like this?</strong> This guide takes four steps, demonstrating an overview of the whole flow and connection between four tools to build a photo map. This guide will hit the main points, highlight how the tools connect up with open data, and I’ll just link to other resources for the details on how to use each.</p> <h2 class="summary-item" id="upload-photos-to-flickr"><a href="#upload-photos-to-flickr">Upload Photos to Flickr</a></h2> <ul> <li>What you need: A photo of a place to map.</li> <li>What you get: Link to the photo page and photo preview.</li> <li>Learn more: <a href="https://www.flickr.com/help/photos/" rel="nofollow">Flickr Help</a></li> </ul> <p>If you don’t have a <a href="https://flickr.com/" rel="nofollow">Flickr</a> account, create one, it’s an easy way to share images. Upload a photo of a place. For our example, we uploaded <a href="https://www.flickr.com/photos/mikel_maron/9420814521/" rel="nofollow">this photo of the iHub in Nairobi</a>, taken during the Uchaguzi election project. We created a <a href="https://www.flickr.com/groups/2274104@N21/" rel="nofollow">Map Kibera group</a> to hold all our collective photos. <em><br/> </em></p> <div class="wp-caption aligncenter" id="attachment_664" style="width: 727px"><a href="https://geojournalism.org/wp-content/uploads/2013/08/9508348007_2c645cceeb_b.jpg"><img alt="Credit: Mikel Maron, Ground Truth Initiative" aria-describedby="caption-attachment-664" class="wp-image-664" decoding="async" fetchpriority="high" height="354" sizes="(max-width: 717px) 100vw, 717px" src="https://geojournalism.org/wp-content/uploads/2013/08/9508348007_2c645cceeb_b.jpg" srcset="https://geojournalism.org/wp-content/uploads/2013/08/9508348007_2c645cceeb_b.jpg 1024w, https://geojournalism.org/wp-content/uploads/2013/08/9508348007_2c645cceeb_b-300x148.jpg 300w" width="717"/></a><p class="wp-caption-text" id="caption-attachment-664">Credit: Mikel Maron, Ground Truth Initiative</p></div> <p><span style="font-size: 13px; line-height: 19px;">From your photo page, click the </span><strong style="font-size: 13px; line-height: 19px;">Share</strong><span style="font-size: 13px; line-height: 19px;"> button, and then the </span><strong style="font-size: 13px; line-height: 19px;">Grab the HTML/BBCode</strong><span style="font-size: 13px; line-height: 19px;"> panel. Select a “Small” image size, and copy/paste the HTML code into a text editor/word processor. We need only the image link, which is within the </span><strong style="font-size: 13px; line-height: 19px;"><img alt="" decoding="async" src="..."/></strong><span style="font-size: 13px; line-height: 19px;"> tag.</span></p> <p>The result you should have is a link to the photo page, and the photo preview. Something like:</p> <pre><code>https://www.flickr.com/photos/mikel_maron/9420814521/ https://farm4.staticflickr.com/3673/9420814521_f71924dd4e.jpg</code></pre> <h2 class="summary-item" id="edit-openstreetmap"><a href="#edit-openstreetmap">Edit OpenStreetMap</a></h2> <ul> <li>What you need: Location of your photo.</li> <li>What you get: OpenStreetMap feature linked to the image.</li> <li>Learn more: <a href="https://learnosm.org/en/" rel="nofollow">LearnOSM</a></li> </ul> <p>Now, over to <a href="https://osm.org/" rel="nofollow">OpenStreetMap</a>. Sign up if needed, and review the basics in <a href="https://learnosm.org/en/" rel="nofollow">LearnOSM</a>. Also, try the iD Walkthrough: navigate to an area, click <strong>Edit</strong> (specifically, click the down arrow, and select “Edit with iD”), and follow along the editing tutorial.</p> <p><strong>Now</strong> open the <strong>View</strong> tab again. Enter the name of the location of your photo, and search. In our case, it’s “iHub”. Look through the search results, and find the correct feature, <em>there might be more than one feature with that name</em>, and then click <strong>View Details</strong> to open the <a href="https://www.openstreetmap.org/browse/node/673988331" rel="nofollow">browse page for that node</a>. This page shows the location and tags for the feature, and in the lower right, click the <strong>Edit Node</strong> link.</p> <p><em>Often you’ll need to add a new feature in OSM, rather than add to an existing feature. Check out the other guides to learn more.</em></p> <div class="wp-caption aligncenter" id="attachment_651" style="width: 727px"><a href="https://geojournalism.org/wp-content/uploads/2013/08/9511330104_a4bdec07e4_b.jpg"><img alt="Credit: Mike Maron" aria-describedby="caption-attachment-651" class="wp-image-651" decoding="async" height="365" sizes="(max-width: 717px) 100vw, 717px" src="https://geojournalism.org/wp-content/uploads/2013/08/9511330104_a4bdec07e4_b.jpg" srcset="https://geojournalism.org/wp-content/uploads/2013/08/9511330104_a4bdec07e4_b.jpg 1024w, https://geojournalism.org/wp-content/uploads/2013/08/9511330104_a4bdec07e4_b-300x152.jpg 300w" width="717"/></a><p class="wp-caption-text" id="caption-attachment-651">Credit: Mike Maron</p></div> <p>In the left panel, click All tags, then the +, to add the tags to link the image on flickr. Add “image”, then the link to the Flickr photo page. It will look like:</p> <pre> image=https://www.flickr.com/photos/mikel_maron/9420814521/</pre> <p>Click <strong>Save</strong>, add a commit message, and click <strong>Save</strong> again.</p> <p><strong>Caveats</strong></p> <p>Important: When you are taking photos, make sure to record which photo goes with which object! It can get confusing if there’s a lot.</p> <h2 class="summary-item" id="extraction-with-overpass-turbo"><a href="#extraction-with-overpass-turbo">Extraction with Overpass Turbo</a></h2> <ul> <li> What you need: A Deep Breath (take one now!)</li> <li>What you get: A GeoJSON file containing images and locations.</li> <li>Learn more: Overpass Turbo wiki page</li> </ul> <p>The OpenStreetMap website presents one view of the data you contribute. The powerful thing about OSM is that you can take the data and use it however you like. Extracting the data from OSM itself, for use in another tool, is what this step is about.</p> <div class="wp-caption aligncenter" id="attachment_652" style="width: 727px"><a href="https://geojournalism.org/wp-content/uploads/2013/08/9508838929_56cae156ed_b.jpg"><img alt="Credit: MIke Maron" aria-describedby="caption-attachment-652" class="wp-image-652" decoding="async" height="365" sizes="(max-width: 717px) 100vw, 717px" src="https://geojournalism.org/wp-content/uploads/2013/08/9508838929_56cae156ed_b.jpg" srcset="https://geojournalism.org/wp-content/uploads/2013/08/9508838929_56cae156ed_b.jpg 1024w, https://geojournalism.org/wp-content/uploads/2013/08/9508838929_56cae156ed_b-300x152.jpg 300w" width="717"/></a><p class="wp-caption-text" id="caption-attachment-652">Credit: MIke Maron</p></div> <p>Open <a href="https://overpass-turbo.eu/?key=image&amp;template=key-type&amp;type=node" target="_blank">Overpass Turbo</a> with the template to search for nodes with key “image”. <em>You can find links for other tags by exploring <a href="https://taginfo.openstreetmap.org/" target="_blank">TagInfo</a>, another great tool I’ll cover in a later skill share.</em> The interface has two panels, on the left the “Query” and the right the “Map”. Search and navigate the map to the area where your features are located. For us, the is “Nairobi”.</p> <p>The query to do the extraction can get complicated; you’ll see the template settings on the left, looking something like.</p> <pre>{{key=image}} {{type=node}}</pre> <p>Now click <strong>Run</strong>. Overpass will work for a few seconds, and then display the results on the map. You can click the points to get more info on each feature. Now click the <strong>Export</strong> menu, then the <strong>Data</strong> panel, and finally <strong>GeoJSON</strong>. This should trigger a download of the results, and a display of the results in the dialog (some browsers won’t automatically download, so copy/paste the GeoJSON from the dialog into a file, and save locally). Note the location of the GeoJSON file, we need it for the next step.</p> <h2 class="summary-item" id="groom-geojson"><a href="#groom-geojson">Groom GeoJSON</a></h2> <ul> <li>What you need: The GeoJSON created with Overpass Turbo.</li> <li>What you get: GeoJSON with image preview links</li> </ul> <p>To make our map, we need not only links to the Flickr page for the uploaded images, but also a link to the preview image itself. The <a href="https://mikelmaron.github.io/geojson-flickr-groomer/" target="_blank">GeoJSON Flickr Groomer</a> is a simple tool to create those links.</p> <div class="wp-caption aligncenter" id="attachment_653" style="width: 727px"><a href="https://geojournalism.org/wp-content/uploads/2013/08/9628249541_81308bae87_b.jpg"><img alt="Credit: Mikel Maron" aria-describedby="caption-attachment-653" class="wp-image-653" decoding="async" height="538" loading="lazy" sizes="auto, (max-width: 717px) 100vw, 717px" src="https://geojournalism.org/wp-content/uploads/2013/08/9628249541_81308bae87_b.jpg" srcset="https://geojournalism.org/wp-content/uploads/2013/08/9628249541_81308bae87_b.jpg 1024w, https://geojournalism.org/wp-content/uploads/2013/08/9628249541_81308bae87_b-300x225.jpg 300w" width="717"/></a><p class="wp-caption-text" id="caption-attachment-653">Credit: Mikel Maron</p></div> <p>Open the GeoJSON file downloaded from Overpass Turbo in your text editor. Copy all the content, and paste into the first text box. <strong>Click here to Run</strong>, then <strong>Download groomed-geojson.json</strong>. Note the location of the GeoJSON file, we need it for the final step.</p> <h2 class="summary-item" id="make-a-map-with-tilemill"><a href="#make-a-map-with-tilemill">Make a Map With TileMill</a></h2> <ul> <li>What you need: The GeoJSON modified by GeoJSON Flickr Groomer.</li> <li>What you get: An interactive map (finally!)</li> <li>Learn more: <a href="https://www.mapbox.com/tilemill/docs/crashcourse/introduction/" target="_blank">TileMill Crash Course</a> and <a href="https://www.mapbox.com/help/#help-mapbox" target="_blank">MapBox Help</a></li> </ul> <p>TileMill is a tool for designing maps. There’s a lot to it, so do check out the Crash Course, and other guides on the TileMill site. <a href="https://www.mapbox.com/tilemill/docs/install" target="_blank">Install TileMill</a>, start it up, and create a new project; uncheck <strong>Default</strong> data. Now, in the lower left, click the <strong>Layers</strong> buton, then <strong>Add Layer</strong>. For the <strong>Datasource</strong> field, browse and find the GeoJSON file downloaded from GeoJSON Flickr Groomer. Click <strong>Save &amp; Style</strong>, and you should see a map of your points on the left side of the screen. To zoom to the area of just your data, reopen the Layers dialog, and click the magnifying lens next to the layer.</p> <div class="wp-caption aligncenter" id="attachment_654" style="width: 727px"><a href="https://geojournalism.org/wp-content/uploads/2013/08/9511708544_e5c3d10335_b.jpg"><img alt="Credit: Mikel Maron" aria-describedby="caption-attachment-654" class="wp-image-654" decoding="async" height="394" loading="lazy" sizes="auto, (max-width: 717px) 100vw, 717px" src="https://geojournalism.org/wp-content/uploads/2013/08/9511708544_e5c3d10335_b.jpg" srcset="https://geojournalism.org/wp-content/uploads/2013/08/9511708544_e5c3d10335_b.jpg 1024w, https://geojournalism.org/wp-content/uploads/2013/08/9511708544_e5c3d10335_b-300x164.jpg 300w" width="717"/></a><p class="wp-caption-text" id="caption-attachment-654">Credit: Mikel Maron</p></div> <p>On the right, is CartoCSS, used to style your map. We want to make some small changes, making the background of the map transparent (by default it’s sea blue). Here’s what our CartoCSS looks like:</p> <pre>Map { background-color: transparent; } #images { marker-width:6; marker-fill:#f45; marker-line-color:#813; marker-allow-overlap:true; }</pre> <p>Now, add <strong>Interactivity</strong>, the dialog is reached by clicking the small hand in the lower left tool set. Click <strong>Full</strong>. Here you can specify what appears when you click on a point. All of the tags for these features from OSM are available, you’ll see them in a list at the bottom of the dialog in “Mustache” tags. We set the content to this below, to show the name of the feature, and a linked photo.</p> <pre>{{{name}}} <a href="%7B%7B%7Bimage%7D%7D%7D"><img alt="" decoding="async" src="href%7D%7D%7D"/></a></pre> <p>The map is ready to share! Sign up for a <a href="https://tiles.mapbox.com/signup" target="_blank">free account on MapBox</a>. Then back in TileMill, click the <strong>Export-&gt;Upload</strong> option in the upper right, configure the settings for the upload (try to minimize the upload size), and <strong>Upload</strong>. You can watch the progress of the export and upload, and then get a link to the map.</p> <p><a href="https://a.tiles.mapbox.com/v3/groundtruth.map-vx5bbbu4/page.html" target="_blank">Here’s ours</a>!</p> <h2 class="summary-item" id="results-and-your-challenge"><a href="#results-and-your-challenge">Results and your challenge</a></h2> <div class="wp-caption aligncenter" id="attachment_655" style="width: 727px"><a href="https://geojournalism.org/wp-content/uploads/2013/08/9511711840_3d97a64423_b.jpg"><img alt="Credit: Mikel Maron" aria-describedby="caption-attachment-655" class="wp-image-655" decoding="async" height="365" loading="lazy" sizes="auto, (max-width: 717px) 100vw, 717px" src="https://geojournalism.org/wp-content/uploads/2013/08/9511711840_3d97a64423_b.jpg" srcset="https://geojournalism.org/wp-content/uploads/2013/08/9511711840_3d97a64423_b.jpg 1024w, https://geojournalism.org/wp-content/uploads/2013/08/9511711840_3d97a64423_b-300x152.jpg 300w" width="717"/></a><p class="wp-caption-text" id="caption-attachment-655">Credit: Mikel Maron</p></div> <p>So this is it! To get the streets background, you’ll need to dive a little more into MapBox hosting configuration. <strong>Try it out on your own, with say, 10 images.</strong> If you have any questions about this guide, suggestions to improve it, or just want to share your results, get in touch. Thanks!</p> <div class="author-shortcodes"> <div class="author-inner"> <div class="author-image"> <img alt="" src="https://geojournalism.org/wp-content/uploads/2013/09/mikel.jpg"/> <div class="author-overlay"></div> </div> <!-- .author-image --> <div class="author-info"> <strong>Mikel Maron</strong> (<a href="https://twitter.com/mikel">@mikel</a>) is a programmer and geographer working for impactful community and humanitarian uses of open source and open data. He is co-founder of <a href="https://groundtruth.in/">Ground Truth Initiative</a>, and of the <a href="https://mapkibera.org/">Map Kibera</a> project. He’s also Founder and President of the <a href="https://hot.openstreetmap.org/">Humanitarian OpenStreetMap Team</a>, having helped to facilitate the OSM response to the Haiti earthquake. He’s travelled widely, organizing projects in India, Palestine, Egypt, Swaziland, and elsewhere. Previously to this, he co-founded Mapufacture and worked on collaborative platforms, geoweb standards, and various applications, with a wide spectrum of organizations from UN and government agencies to anarchist hacker collectives. </div> <!-- .author-info --> </div> <!-- .author-inner --> </div> .author-shortcodes <meta content="text/html; charset=utf-8" http-equiv="Content-Type"/> <p>The post <a href="https://geojournalism.org/2013/08/how-to-map-photos-using-openstreetmap-and-tilemill/">How to Map Photos Using OpenStreetMap and TileMill</a> appeared first on <a href="https://geojournalism.org">geojournalism.org</a>.</p> 268 https://geojournalism.org/2013/08/balloon-mapping-how-to-make-your-own-low-flying-satellite/ Willie Shubert Wed, 14 Aug 2013 21:10:57 +0000 Crowdsourcing Maps balloon mapping cartography map design satellite imagery https://geojournalism.oeco.org.br/?p=264 <p>Balloon mapping provides individuals or groups with a low-cost means to create a running record of events in map form, one that is temporally accurate and easy to share.&#160; What is Balloon Mapping? Today, aerial imagery&#8212;pictures that are taken from above the Earth&#8217;s surface&#8212;are typically made by satellites and planes. &#160;But in the days before [&#8230;]</p> <p>The post <a href="https://geojournalism.org/2013/08/balloon-mapping-how-to-make-your-own-low-flying-satellite/">Balloon Mapping: How to make your low-flying satellite</a> appeared first on <a href="https://geojournalism.org">geojournalism.org</a>.</p> <p>Balloon mapping provides individuals or groups with a low-cost means to create a running record of events in map form, one that is temporally accurate and easy to share. <span id="more-264"></span></p> <h2 class="summary-item" id="what-is-balloon-mapping"><a href="#what-is-balloon-mapping">What is Balloon Mapping?</a></h2> <div class="wp-caption alignleft" id="attachment_232" style="width: 310px"><img alt="" aria-describedby="caption-attachment-232" class="size-medium wp-image-232" decoding="async" height="225" loading="lazy" src="https://dev.cardume.art.br/toolkit/wp-content/uploads/2013/08/Balloon-Mapping-Intro-Image-300x225.jpg" title="Tandem balloon Mapping in a community garden" width="300"/><p class="wp-caption-text" id="caption-attachment-232">Credit: Knowledge Commons DC</p></div> <p>Today, aerial imagery—pictures that are taken from above the Earth’s surface—are typically made by satellites and planes.  But in the days before such inventions, balloons and kites we’re a handy way to obtain a view from the sky. Climate scientists have long attached weather sensors called <i>radiosonde </i>to obtain measurements from various altitudes. The concept of balloon mapping is pretty simple, attach a camera to something that flies and take pictures of the ground. While the idea of floating something in the sky is indeed simple, high level applications include Google’s <a href="https://www.google.com/loon/" target="_blank">Project Loon</a> — focused on delivering long-range Wi-Fi via balloon and long-term surveillance missions run by the <a href="https://www.wired.com/dangerroom/2011/10/giant-blimp-dwarfs-truck/" target="_blank">US military</a>.</p> <p>Balloon mapping provides individuals or groups with a low-cost means to create a running record of events in map form, one that is temporally accurate and easy to share. This tutorial, made with assistance from the <a href="https://publiclab.org/wiki/balloon-mapping" target="_blank">Public Laboratory</a>, will take you through a process of building and deploying a do-it-yourself satellite.</p> <h2 class="summary-item" id="when-is-it-useful"><a href="#when-is-it-useful">When is it useful?</a></h2> <p>In most cases, freely available aerial imagery is the best choice for a journalist illustrating a story with a picture from the sky. However, satellite imagery made available through companies like Google or Bing Maps are typically one to three years old and often feature winter images to minimize visible area covered by trees.  For breaking news stories like a natural disaster or a protest, obtaining recent or near real-time satellite imagery is critical and expensive.  A tethered balloon on the other hand is able to fly at much lower altitude and collects images at around 3 centimeters spatial resolution (3cm in real space equals one pixel) as opposed to a 50cm average in Google Earth and 250m in LANDSAT satellite imagery.</p> <p>Balloon and kite mapping is an appropriate tool when you need high resolution, time sensitive imagery from a potentially contentious location. Balloon mapping has already been used to document effects of the 2011 Deepwater Horizon Oil Spill, the size of Occupy Wall Street protests, and to contest official maps in Lima, Peru that left residents of informal settlements of the official city map.</p> <p>According to the Public Laboratory, mapping can be used by those in power to control territorial narratives. “Grassroots mapping attempts to invert this dynamic by using maps as a mode of communication and as evidence for an alternative, community-owned definition of a territory.”</p> <h2 class="summary-item" id="required-materials"><a href="#required-materials">Required Materials</a></h2> <p>The engineering of a balloon mapping rig is very simple and intuitive. The materials—except for helium—can be created relatively cheaply (about $150USD upfront) and reused. Basic elements include: a point and shoot camera with continuous mode, a weather balloon, high-strength lightweight string (kite string or fishing line) with a reel, rubber bands, a plastic bottle, zip ties, and tape. Alternative constructions include materials like Mylar emergency blankets instead of balloons and a trash cans for housing the camera. The Public Laboratory <a href="https://store.publiclab.org/products/balloon-mapping-kit" target="_blank">sells a kit</a> that includes most of the required materials but you can also assemble your own.</p> <div class="wp-caption aligncenter" id="attachment_229" style="width: 310px"><img alt="Credit: Public Laboratory" aria-describedby="caption-attachment-229" class="size-medium wp-image-229" decoding="async" height="300" loading="lazy" src="https://dev.cardume.art.br/toolkit/wp-content/uploads/2013/08/Balloon-Mapping-Kit-300x300.jpg" width="300"/><p class="wp-caption-text" id="caption-attachment-229">Credit: Public Laboratory</p></div> <p>Aside from the materials listed in the kit above, you need is a good, cheap camera that has a continuous shooting mode. A continuous (or burst) camera mode is vital since you will want to collect multiple images while flying and this setting allows you to do so. A list of suitable cameras can be found <a href="https://publiclab.org/wiki/camera-selection">here</a>. Physical and digital hacks to ensure continuous photography will be covered in the following flight preparation &amp; construction step.</p> <p>You will also need helium to fill and lift the balloon. Helium is lighter than air so it floats to achieve its natural equilibrium. The size of the balloon and the amount of helium you use determines how much your balloon will be able to lift.  The 2 meter diameter balloon included in Public Lab’s balloon mapping kit can lift 3288.5 grams. You must consider the weight of your all in-air equipment to determine if your rig will fly. For other size balloons <a href="https://www.chem.hawaii.edu/uham/lift.html">this set of charts</a> outlining the physical properties of lighter-than-air gases is useful.</p> <p><strong>Flight Preparation &amp; Construction</strong></p> <p>There are two distinct elements to prepare for prior to launching your flying camera rig. First, it is important to research the location you are going to map including the regulations governing tethered balloon flying and  the geography of the area. Going on a scouting trip can help you identify potential obstacles like trees/power lines and give you a feel for local weather conditions. Second, you must gather and assemble the material components of the balloon mapping rig.</p> <p>When researching the area you plan to map, it is a good idea to visit first before you fly. Tell the people who live where you will be mapping that you will be there, print out a satellite map of the area to take notes, and most importantly research the government rules that apply. In the US, tethered balloon flight is regulated by the Federal Aviation Administration (FAA) and they have rules governing the size of the balloon, the amount of weight it can carry, and how high the balloon can fly without explicit government permission.</p> <p>Local weather conditions are very important since high-wind can make capturing clear images from a stable camera very difficult. In such conditions <a href="https://www.publiclab.org/wiki/kite-mapping">a kite may be better</a>. Remember don’t put anything in the air you aren’t comfortable losing.</p> <p>Once you have figured out what you want to map and researched area and regulations governing flight, you can assemble your materials for flying. After selecting and testing your camera for continuous mode, you can build a light weight rig to protect the camera from falls and provide additional stability. The cheapest option is to <a href="https://www.publiclab.org/wiki/pet-bottle-rubber-band-rig">build this housing from a PET plastic bottle</a> and rubber bands.</p> <p>Video and images courtesy of the Public Laboratory:</p> <div class="wp-caption aligncenter" id="attachment_230" style="width: 310px"><img alt="Credit: Matthew Lippincott, Public Laboratory" aria-describedby="caption-attachment-230" class="size-medium wp-image-230" decoding="async" height="225" loading="lazy" src="https://dev.cardume.art.br/toolkit/wp-content/uploads/2013/08/Balloon-Mapping_PET-bottle-image-300x225.jpg" width="300"/><p class="wp-caption-text" id="caption-attachment-230">Credit: Matthew Lippincott, Public Laboratory</p></div> <p style="text-align: center;"><iframe allowfullscreen="allowfullscreen" frameborder="0" height="360" loading="lazy" src="//www.youtube.com/embed/t96Za2l0VjU" style="margin: 0 auto;" width="480"></iframe></p> <p>Now that you have your rig built, it’s time to fill up the balloon (this can be done on-location or if logistically feasible beforehand). Having a teammate is really helpful for this step because the balloon will fill up really big and needs to be held. One person should fill the balloon and the other should hold it as it fills to make sure it doesn’t fly away or hit something sharp.</p> <p>With a full balloon in hand, it is time to attach the housing to the balloon. The simplest way to do this is to attach the swivel clips included in the kit to the line tethering the balloon. Without the clips you can also use a piece of line to tie the rig to the bottom of the balloon but make sure it is tight so that it doesn’t fall.</p> <p>The final piece of the puzzle necessary to set up before flying is to place the camera in its housing with a continuous shooting mode engaged. Depending on the type of camera you have, you can either physically press the shutter button with a piece of cardboard and a rubber band or you can enable a time lapse mode in your camera by using an existing feature or (if you  have a point-and-shoot Canon camera and are technically inclined) adding the <a href="https://chdk.wikia.com/wiki/CHDK_1.2.0_User_Manual">Canon Hack Develop Kit</a> (CHDK) to your SD card.</p> <h2 class="summary-item" id="piloting-stabilization"><a href="#piloting-stabilization">Piloting &amp; Stabilization</a></h2> <p>Once your balloon rig is set up and taking pictures, let it fly!  This step is where the fun and the finesse begin. You can control the altitude of the balloon using the reel that is holding the line. The more line you release the higher the balloon can fly. The shorter the sting, the closer the balloon stays to the ground. The experience is kind of like fishing in the sky.  The altitude of the balloon is important because pictures from similar heights can be stitched together to create an image equivalent to one zoom level on a map.</p> <div class="wp-caption alignright" id="attachment_231" style="width: 310px"><img alt="Azmuth Illustration" aria-describedby="caption-attachment-231" class="size-medium wp-image-231" decoding="async" height="225" loading="lazy" src="https://dev.cardume.art.br/toolkit/wp-content/uploads/2013/08/Azmuth-Illustration-300x225.jpg" width="300"/><p class="wp-caption-text" id="caption-attachment-231">Credit: Public Laboratory</p></div> <p>At first keep you balloon at a low altitude and walk the area you want to map. The height of the balloon is roughly equivalent to the ground area you are recording, so a balloon 10 meters in the area will capture about 10 square meters. Walking a predetermined path, or transect, will ensure that you can capture all of the ground area you want.</p> <p>Once you have done a set of transects at one fixed altitude, give the balloon more line and let it fly higher. The higher it is, the more it captures (but at less resolution). You can repeat this process as many times as you want. The only limits you have are the line distance, the disk space on your camera, and your camera’s battery life.</p> <p>As you walk your transects it is important to watch the stability of your camera rig. The best images are captured when the rig is stable and pointed at a 90 degree angle towards the ground. A swinging rig is a bad sign since obliquely angled images will have to be stretched to make a flat, planimetric map.</p> <p>Techniques for maximizing stabilization are grounds for experimentation amongst the balloon mapping community. Some simple solutions include adding multiple lines to one balloon to increase the tension and reduce the influence of the wind. This technique works well for low-altitude balloon mapping but is difficult when the balloon is high in the air. It also requires an almost dance like coordination between the two balloon pilots. A more intricate solution is the <a href="https://www.publiclab.org/wiki/picavet-rigging">picavet system</a> for stabilization. It requires some skill and weights more but it works well especially for mappers using high-end cameras.</p> <h2 class="summary-item" id="image-processing"><a href="#image-processing">Image Processing</a></h2> <p style="text-align: center;"><img alt="Credit: Public Labratory" class="wp-image-234 aligncenter" decoding="async" height="481" loading="lazy" src="https://dev.cardume.art.br/toolkit/wp-content/uploads/2013/08/MapMill-Good-Image-Chart.png" width="353"/></p> <p>This step is where your pictures become a map. Depending on the amount of time you have been flying your balloon, you should have lots of images and many of them won’t be clear enough to be useful. The best images are clear–without distortion from shaking or overexposure–and pointed vertically–directly toward the ground. It is also helpful to prioritize good images that cover the largest area possible.</p> <p>You can select pictures on your desktop using an image preview features or you can download a copy of <a href="https://mapmill.org/">MapMill</a> to enable the Public Lab community to help identify useful images.</p> <div class="wp-caption aligncenter" id="attachment_233" style="width: 400px"><img alt="Map Stiching Example" aria-describedby="caption-attachment-233" class="wp-image-233" decoding="async" height="221" loading="lazy" src="https://dev.cardume.art.br/toolkit/wp-content/uploads/2013/08/Map-Stiching-Example.gif" width="390"/><p class="wp-caption-text" id="caption-attachment-233">Credit: Sam Pepple, Sample Cartography</p></div> <p>Once you have selected a set of useable images, you can then begin the process of stitching these pictures together into a bigger map. You can do this using image processing software like Adobe Photoshop or by using the Public Lab’s MapKnitter browser-based editor. MapKnitter allows you to upload, overlay, stretch, and resize your photos with a Google Maps satellite view as a reference.</p> <p style="text-align: center;"><iframe allowfullscreen="allowfullscreen" frameborder="0" height="360" loading="lazy" src="//www.youtube.com/embed/NOikqxIIFBc" width="480"></iframe></p> <p>By using MapKnitter, you will also have many tools available for exporting and sharing the maps you just made with the world.</p> <div class="author-shortcodes"> <div class="author-inner"> <div class="author-image"> <img alt="" src="https://photos1.meetupstatic.com/photos/member/2/7/7/f/member_18490111.jpeg"/> <div class="author-overlay"></div> </div> <!-- .author-image --> <div class="author-info"> <strong>Willie Shubert</strong> is the Senior Project Coordinator for Internews’ Earth Journalism Network. As a coordinator of a global network of environmental journalists, Willie helps make tools that enable people to connect with each other, find material support, and amplify their local stories to global audiences. In his previous position at National Geographic Magazine, he coordinated translation for the magazine’s 32 local language partners. He holds a degree in Geography from Humboldt State University with concentrations in cartography, environmental economics, and Chinese Studies. Outside of work, he devotes his time to the development of a free school dedicated to community building through education and to collaborative mapping and audio projects. </div> <!-- .author-info --> </div> <!-- .author-inner --> </div> .author-shortcodes <meta content="text/html; charset=utf-8" http-equiv="Content-Type"/> <p>The post <a href="https://geojournalism.org/2013/08/balloon-mapping-how-to-make-your-own-low-flying-satellite/">Balloon Mapping: How to make your low-flying satellite</a> appeared first on <a href="https://geojournalism.org">geojournalism.org</a>.</p> 264 https://geojournalism.org/2013/08/map-styles/ Gustavo Faleiros Fri, 09 Aug 2013 15:25:53 +0000 Design Maps Visualization map design maps https://dev.cardume.art.br/toolkit/?p=179 <p>Most available databases have some element of location to them. According to officers working at the open data portal of the US government, around 90% of their datasets contain geographical information, ranging from streets names to precise coordinates. In this tutorial, we will show the different kind of maps you can use to convey information [&#8230;]</p> <p>The post <a href="https://geojournalism.org/2013/08/map-styles/">Choosing the right kind of map for your story</a> appeared first on <a href="https://geojournalism.org">geojournalism.org</a>.</p> <p>Most available databases have some element of location to them. According to officers working at the open data portal of the US government, around 90% of their datasets contain geographical information, ranging from streets names to precise coordinates. In this tutorial, we will show the different kind of maps you can use to convey information and enable users to interact with and explore the environmental data you’ve gathered to support your story.</p> <h2 class="summary-item" id="points-of-interest"><a href="#points-of-interest">Points of interest</a></h2> <p>Points are the simplest symbol used to make maps. You can simply pin your map with a specific location you would like to highlight or you can include many points, or icons on several locations to represent your data.</p> <p>On the example below, done on <a href="https://geojournalism.org/tools/fusion-tables/" title="Fusion Tables">Google Fusion Tables</a>, the species of Butterflies are mapped in Costa Rica.</p> <p><iframe frameborder="no" height="350" loading="lazy" scrolling="no" src="https://www.google.com/fusiontables/embedviz?q=select+col12+from+1yooILLPC5cFA9y2TEedmBkHA8aO-JbpbcXsBeq4&amp;viz=MAP&amp;h=false&amp;lat=10.901887452028856&amp;lng=-85.40865571411138&amp;t=1&amp;z=10&amp;l=col12&amp;y=2&amp;tmplt=2" width="820"></iframe></p> <h2 class="summary-item" id="polygon-maps"><a href="#polygon-maps">Polygon Maps</a></h2> <p>These maps are useful when area, boundaries, shapes or limits need to be represented. A classical example is world boundaries map or a map representing the different natural physiology within a protected area</p> <div class="wp-caption aligncenter" style="width: 692px"><img alt="" decoding="async" height="477" loading="lazy" src="https://upload.wikimedia.org/wikipedia/commons/e/e4/Last_glacial_vegetation_map.png" width="682"/><p class="wp-caption-text">World Vegetation Map with data of the National Geophysical Data Center. Courtesy of Wikimedia Commons</p></div> <h2 class="summary-item" id="heat-maps"><a href="#heat-maps">Heat Maps</a></h2> <p>When a concentration of occurrences or points of interest happen in a same location, it is possible to group certain areas together using an average value over an area. Also known as isoline maps, and used often for visualizing weather data, “heat” maps can used to visualize particularly intense concentrations evident in your data.</p> <p>The example bellow shows the biodiversity hotspots around the globe by measuring biomass density.</p> <div class="wp-caption aligncenter" style="width: 810px"><img alt="" class="" decoding="async" height="473" loading="lazy" src="https://e360.yale.edu/images/slideshows/gallery_ncsu_biodiversity_hotspots_global.jpg" width="800"/><p class="wp-caption-text">The red areas represent those with highest species density and the blue territories , the lowest. Courtesy of Saving Species 2012</p></div> <h2 class="summary-item" id="bubble-map"><a href="#bubble-map">Bubble Map</a></h2> <p>This kind of map is similar to a point map with the difference that you scale the size of the points according to numerical values, creating the a bubble look to highlight events on specific location. This map style is also referred to as a “graduated symbols” map since a designer is not limited to circles for their symbols.</p> <p>On the following example, the locations of forest fires are scaled according to the number of events. This map was done on <a href="https://geojournalism.org/tools/tableau-public-software/" target="_blank" title="Tableau">Tableau Public Software</a>.</p> <div class="wp-caption aligncenter" style="width: 692px"><img alt="" decoding="async" src="https://www.tableausoftware.com/public/sites/default/files/Bubble%20Map%20Forest%20Fires.png" width="682"/><p class="wp-caption-text">The size of the bubbles over the map represent the amount acres burned, showing that the West Coast of US is more affected over a period of 10 years. Image: Courtesy Tableau Public</p></div> <h2 class="summary-item" id="cloropleth-map"><a href="#cloropleth-map">Cloropleth map</a></h2> <p>Coloring polygons like country boundaries according to the values represented on the map is the <a href="https://en.wikipedia.org/wiki/Choropleth_map" target="_blank">cloropleth map</a>. This classic form of cartography maybe the most well recognized map style. Political maps like the ones that show divisions between Republicans and Democrats in the US are on every TV newsshow and newspaper. But there are many more ways to use this style map. One of them is applying a gradient respecting a numerical range. To choose colors, we recommend the tool <a href="https://geojournalism.org/tools/color-brewer/" target="_blank" title="Color Brewer">Color Brewer</a>.</p> <p>Here is an example of a cloropleth done in the project InfoAmazonia showing the quantity of heads of cattle per municipality in the north of Brazil</p> <p><iframe frameborder="0" height="480" loading="lazy" src="https://infoamazonia.org/en/embed/?no_stories=1&amp;map_id=2530&amp;width=820&amp;height=480&amp;lat=-7.710991655433229&amp;lon=-59.23828124999999&amp;zoom=5" width="820"></iframe></p> <h2 class="summary-item" id="cartogram"><a href="#cartogram">Cartogram</a></h2> <p>A cartogram distorts the size of shapes on the map according to the the values they represent. The example bellow reshape the size of the countries according to their carbon emissions. As you can see immediately, US and China get really swollen while the whole African continent almost disappear</p> <div class="wp-caption aligncenter" style="width: 690px"><img alt="" decoding="async" src="https://www.viewsoftheworld.net/wp-content/uploads/2010/11/CarbonEmissionMap_2009.jpg" width="680"/><p class="wp-caption-text">Map originally published at <a href="http://www.viewoftheworld.net" rel="nofollow">http://www.viewoftheworld.net</a></p></div> <div class="author-shortcodes"> <div class="author-inner"> <div class="author-image"> <img alt="" src="https://media.licdn.com/mpr/mpr/shrinknp_200_200/AAEAAQAAAAAAAAlOAAAAJGJmNmMxZTFiLWY5ODUtNGFlNy05MTE0LTZjNDk3ZWJmNWRkMA.jpg"/> <div class="author-overlay"></div> </div> <!-- .author-image --> <div class="author-info"> <strong>Gustavo Faleiros</strong> is an environmental journalist and media trainer who specializes in data-driven journalism. In 2012, he launched <a href="https://infoamazonia.org/" target="_blank">InfoAmazonia</a>, a digital map that uses satellite and other publicly available data to monitor the Amazon rainforest. </div> <!-- .author-info --> </div> <!-- .author-inner --> </div> .author-shortcodes <meta content="text/html; charset=utf-8" http-equiv="Content-Type"/> <p>The post <a href="https://geojournalism.org/2013/08/map-styles/">Choosing the right kind of map for your story</a> appeared first on <a href="https://geojournalism.org">geojournalism.org</a>.</p> 179