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<?xml-stylesheet type="text/xsl" href="http://blogs.esri.com/Info/utility/FeedStylesheets/rss.xsl" media="screen"?><rss version="2.0" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:slash="http://purl.org/rss/1.0/modules/slash/" xmlns:wfw="http://wellformedweb.org/CommentAPI/"><channel><title>ArcGIS Explorer Blog : Raster transparency</title><link>http://blogs.esri.com/Info/blogs/arcgisexplorerblog/archive/tags/Raster+transparency/default.aspx</link><description>Tags: Raster transparency</description><dc:language>en</dc:language><generator>CommunityServer 2.1 SP2 (Debug Build: 61120.2)</generator><item><title>Raster Transparency in Explorer 480</title><link>http://blogs.esri.com/Info/blogs/arcgisexplorerblog/archive/2008/07/23/raster-transparency-in-explorer-480.aspx</link><pubDate>Thu, 24 Jul 2008 02:15:00 GMT</pubDate><guid isPermaLink="false">8296249d-4d69-4913-b1e7-14b85fcd9fb0:2384</guid><dc:creator>ArcGIS-Explorer-Team</dc:creator><slash:comments>0</slash:comments><comments>http://blogs.esri.com/Info/blogs/arcgisexplorerblog/comments/2384.aspx</comments><wfw:commentRss>http://blogs.esri.com/Info/blogs/arcgisexplorerblog/commentrss.aspx?PostID=2384</wfw:commentRss><description>&lt;P&gt;One of the new features introduced with ArcGIS Explorer 480 is the ability to set any color in a raster image transparent. This is very handy when working with georeferenced images with "no data" values. Have a &lt;A class="" title="Play the video" href="http://downloads2.esri.com/edn/mediaCenter/wmv/ArcGISExplorer_RasterTransparency.wmv" target=_blank&gt;look at the video&lt;/A&gt;, then follow along in this post.&lt;/P&gt;
&lt;P&gt;&lt;A class="" title="Play video" href="http://downloads2.esri.com/edn/mediaCenter/wmv/ArcGISExplorer_RasterTransparency.wmv" target=_blank&gt;&lt;IMG src="http://blogs.esri.com/Info/photos/arcgisexplorer/images/2394/original.aspx" border=0&gt;&lt;/A&gt;&lt;/P&gt;
&lt;P&gt;Let's take a closer look. First, we've added a local raster file, in this case a TIF image that was used during the California fire response last year. To add&amp;nbsp;a local raster go to File, then Open, and choose Rasters, and then browse for the file you want. &lt;/P&gt;
&lt;P&gt;In this particular&amp;nbsp;file you will&amp;nbsp;see that we have black areas representing&amp;nbsp;"no data" surrounding the image, and blocking the view of the underlying basemap information. &lt;/P&gt;
&lt;P&gt;&lt;IMG src="http://blogs.esri.com/Info/photos/arcgisexplorer/images/2395/original.aspx" border=0&gt;&lt;/P&gt;
&lt;P&gt;To set the black areas in the image&amp;nbsp;transparent, first open&amp;nbsp;the raster layer&amp;nbsp;properties. To do this, right click the layer in Contents, then choose Layer Properties.&lt;/P&gt;
&lt;P&gt;&lt;IMG src="http://blogs.esri.com/Info/photos/arcgisexplorer/images/2396/original.aspx" border=0&gt;&lt;/P&gt;
&lt;P&gt;In the layer properties, choose Raster Background. You can specify the&amp;nbsp;transparent color&amp;nbsp;in one of two ways, by typing in the actual RGB values,&amp;nbsp;or by clicking on the image on the map. It's easiest just to click on the color you want transparent in the raster.&lt;/P&gt;
&lt;P&gt;&lt;IMG src="http://blogs.esri.com/Info/photos/arcgisexplorer/images/2397/original.aspx" border=0&gt;&lt;/P&gt;
&lt;P&gt;After we apply the changes, you'll see&amp;nbsp;that we've&amp;nbsp;turned the black RGB values transparent, and created a much nicer overlay.&lt;/P&gt;
&lt;P&gt;&lt;IMG src="http://blogs.esri.com/Info/photos/arcgisexplorer/images/2398/original.aspx" border=0&gt;&lt;/P&gt;
&lt;P&gt;For more information,&amp;nbsp;see the &lt;A class="" title="Raster Background Color Help topic" href="http://services.arcgisonline.com//arcgisexplorer480/help/raster_background_color.htm" target=_blank&gt;Raster Background Color Help&lt;/A&gt; topic.&amp;nbsp;&lt;/P&gt;&lt;img src="http://blogs.esri.com/Info/aggbug.aspx?PostID=2384" width="1" height="1"&gt;</description><category domain="http://blogs.esri.com/Info/blogs/arcgisexplorerblog/archive/tags/video/default.aspx">video</category><category domain="http://blogs.esri.com/Info/blogs/arcgisexplorerblog/archive/tags/480/default.aspx">480</category><category domain="http://blogs.esri.com/Info/blogs/arcgisexplorerblog/archive/tags/Raster+transparency/default.aspx">Raster transparency</category><category domain="http://blogs.esri.com/Info/blogs/arcgisexplorerblog/archive/tags/Rasters/default.aspx">Rasters</category></item></channel></rss>