Google Earth KML

This week was pretty straight forward and simple compared to previous lessons. ( A well needed breather before out final project, perhaps?)

We had to take a mxd from a previous lesson (Module 10 Dot Density map) and convert it into a KML file that allows the information to be displayed in Google Earth (or another similar program).

The only issue I had was going back to an old problem with the dot map, having the dots display onling in urbanized areas. ArcGIS kept crashing everytime I attempted to display it. This time, I got it to work. Either because I reduced the amount of information on the map (no background color, etc.) or because I played with the size of the dots and the number of people each dot represented. Though it did take a good 5 minutes to draw. Once I had the needed elements on my layout displayed, I saved then converted the file via the Map to KML tool in Arc.Once a KML file is created, it's matter of double clicking and displays nicely in Google Earth.

After that, we had to create a tour of the major cities in South Florida. This was also very easy. Clicking the camera button on the tool bar and then clicking the record button. Whatever we do while it's recording, is recorded. Though I had to do it a few times until I had the tour I liked. There was also the trick of displaying and not displaying features, like the pins for the cities or the dots. The trick was find the right moment to uncheck them as the map transitioned to a new area. It's cool how Google Earth does the flying bit. Almost makes any tour look like a professional piece of work. Once in the respective cities, I tried to do a little flying around using the w-a-s-d layout (PC games do matter...).

The other aspect of this lesson was discussing VGI. Google Earth is a tool that seems to be made for anyone to create a basic map. You can add photos, points of interest,etc and share them with a community. If you know how to create KML files, you can go a step further and really create something that can be easily shared with others. I like the open source aspect of it. This is where ESRI fails and companies like Google, Open Street maps or programs like Q-Gis do well. Giving people the ability to map what they want. It's obvious ESRI is attempting to compete with their ArcGIS online and their ArcGlobe, obviously though ESRI is more geared towards organizations that need this tools. However, I'll venture to say that as mapping technologies become more streamlined and easier to access, more and more organizations might opt for open source over paid subscriptions.

Google Map Image with Dot Density layer and related information (legend, etc.)

Geo-Referencing

This week's lab focused on geo- referencing, where by we take un-referenced data (i.e. no geographical projection). We had to take raster data create a reference for it. The data consisted of aerial photos of the UWF campus near Pensacola, Florida. For our purposes we referenced in a basic but effective way. And as beginners in GIS, basic is where we start.

The process works by adding data that is already referenced. In this case, polygons and polylines of roads and buildings on the campus. We then added the raster data. Of course the raster doesn't line up. So we enabled the georeference tool bar. (Everything in ArcGIS comes down to the toolbar). In the tool bar we can first get the raster data to appear in the same space as the buildings/roads layer by selecting Fit to Layer. Then we enable the points. Using the buildings/roads layer, we can connect various points to points on the raster data. I can see the corner of a building, and connect it to it's corresponding polygon. You need to start with the unreferenced data and link it to the referenced data. You need to have at least 5 points.We can then check something called the RIMS error, this will tell us how close those two points are. The error should be under 15. I was able to get the error around 4 on the first raster while still making sure it looked accurate. Having it look accurate is as important as getting a good error value. So one needs to find the right balance. This balance is helped along by using polynomial transformation. There are three levels and the transformation helps to warp the raster data to the points. It can help create a more accurate look but if you use higher levels (as I discovered) it can stretch the raster out and distort it in various ways. The northern half of UWF used a level 1 transformation where as the southern hald used a level 2. Level three really distorted the image. After creating and deleting links I finally got something I felt good with.

We then had to create a buffer zone around an Eagle's nest using the multibuffer tool. This was the easiest part. Input, ouput boom...buffer zone! multi because we created two in one, 330 ft and 600 ft. There was no base map for where the eagles nest is. So I had to add a basemap..for some reason, every time I exported it as a jpeg, it distorted and created a pixalted green mess. I couldn't figure that out. We also used the editing tool to digitize shapes on the map. In our case, the gym and a road. The road was a polyline and the gym, a polygon. I had done this in the past using one of the free ESRI courses which has you digitize a lake. The tool is a little tricky. With the gym, I first tried making a square for each part of the building, but it was hard to line them up and merge them. I went on YouTube, find a viedo and realized there was a way to do it in one sweep...make a lot of little points that match the outline. Though, it didn't come out perfectly, I felt like it worked great.

The next part was the part that you can impress people with the most...no one cares that can you do an awesome job analyzing the best place to set this up or geo code, no the thing that gets the lay people interested are 3D maps! We put our now referenced raste data along with a DEM feature class in Arc Scene. Using the DEM plus the base heights of the buildings we were able to create a 3D map of UWF. This is actually a fun process that I really enjoyed in my Carto class. And your friends often say...ooooh...aaahh....even though in reality the process do it is quite simple despite the number of steps.

Overall this lap helped us to better understand some of the basic mechanics of ArcGIS and how georeferences can be created when none are found. As I near the end of the course, I feel more confident in using ArcGIS...I'm also happy I saved all of those pdfs on my pc so I can look them up when in doubt!

3D Models

This week we had to learn and understand how to create 3D models in arcgis. This was actually quite fun and I felt like I was learning the details and methods behind programs like Google Earth.

In the lab we mostly followed the ESRI training directions and then followed along on the pdf. We learned how to create 3d models using tools such as extrusion. The ESRI training sections are really good at taking you step by step of the various tools in Arc that you can use. At the end of the day, I learned how to take any scene (in which I can create a Z value based on elevation or height) and create a 3d representation.

If I had a choice, I'd stick to 2d maps. Though 3d maps can display information in interesting ways, I feel that they don't have much practical value. Ultimately ArcGIS is about Data anaylsis, and though there are times in which a proper visualization can  improve this process, those times are limited. Personally, I feel 3d models best work for 2 situations: 1) Seeing something that you can't normally see and 2) keeping people interested.

As for number 1, that can apply to maps that have subterrian information, such as the first map we looked at. There I could see that types of rock and the well depths. Also it can apply to visualizing non spatial information in a spatial way such as the property prices for the parcels map.

3d maps definitely are interesting to look at and will keep people's attention. That being said, it's hard to think of situations in which 3d maps provide better information than a 2d map. And unless you're concerned with the actual physical shape of geographic information, it almost seems unnecessary. But ultimately, making 3d maps are fun and look really cool.