September and October sure went fast. We on the Mapping Center team have been very busy working on mapping projects, and have not spent as much time here--but we're finding a balance and will be getting more good blogs done soon (several are in the pipeline). This post's topic is important because many of the questions we get on Ask a ...

A common question we receive goes something like, 'How can I use symbols from the Geologic Mapping Template with my database?'  The solution is simple, once you have downloaded the geologic mapping template, follow these steps to add its representation symbology to your geodatabase: Save the representation rules from the template ...

In the next couple of blog posts, we want to explain a bit about the two tools you can use to create buffers in ArcGIS. Buffers are used not only in analysis of distances and areas around point, line and area features, they are also used in mapping to achieve a number of cartographic effects, such as coastal vignettes. Since there are two tools ...

A couple of weeks ago, Aileen wrote a blog post called ''About geographic transformations and how to choose the right one''. In it, she described many of the parameters that you can set for map projections.  Two that were not mentioned were angular and linear units, so I thought it might help to describe them here. Angular units in the ...

In a blog entry posted last week called Filling and clipping a raster, Aileen described how to fill in holes in a ''bad DEM'' using data from an existing ''good DEM'', then clip the filled DEM to the outline of a feature. The blog post suggested using some ArcGIS geoprocessing tools that are available with the Spatial Analyst extension. As with ...

Sometimes you want to use raster data, like a digital elevation model (DEM), but it doesn't have the same exact extent as the area you are mapping. For example, if I use gtopo30 and ''countries'' data (available on the ESRI Data and Maps CD) to create map of the Pacific Northwest, the coastline boundaries do not coincide. In some places the ...

This post, is to announce the release of a map template for historical GIS called Historical GIS:  Boston 1775. If you’ve never given historical GIS a second, or a first thought, you might find the contents interesting and maybe even applicable to your work. Consider that the vast majority of GIS data is historical, even if it’s only a few ...

You will often be prompted to select the geographic transformation when you are projecting data or setting the projection of a data frame in a map document. Here are some concepts that might help you understand what this is all about AND how to make the right selection. First, ''geographic coordinates'' are expressed in terms of latitude and ...

From time to time we've had to create some building footprint data. A colleague was in my office yesterday looking at the map to the right, and remarked that he thought that adding building footprints to maps ''humanizes'' the map. An interesting observation, and one that I'm not inclined to argue against. We've learned a few tricks for making ...

Sometimes you will find that some annotation you had thought you produced is missing. You can add this missing annotation into your existing annotation feature class without having to recreate all the annotation. The approach you take will depend on whether you are creating standard annotation or feature-linked annotation. Standard annotation ...