Introduction
What is GIS? That is, is it just software. What did Dr. Christina Hupy stress when she spoke about what defines what exactly constitutes GIS?- A GIS is not simply a software packages. Instead it is a combination of software, data, geospatial information, satellites/remote sensing, and people. It is a system of understanding, not an individual classification of software.
What makes open source GIS (QGIS) different than proprietary (ESRI) GIS?
- Open source GIS is developed entirely by the community, for the community, to enhance the functionality of GIS. Essentially, by removing as direct a profit motive (or any profit motive at all), and allowing anyone to develop the software, development can occur extraordinarily fast as compared to proprietary software. The cost of rapid multi-directional development is the concept of direction, which is more established in developments such as ESRI.
What are advantages and disadvantages between the two?
Why is Open Source GIS important to the UAS industry? That is, speculate upon your own experiences and goals to relate how this software could open doors and markets where proprietary GIS keeps doors closed.
- The clear advantage of open source is that it can be developed in any given direction whenever it needs to be. The lack of central authority allows for development to fringe out from the central concept. Over time, this means open source projects can become extremely functional for a variety of tasks. This is a massive advantage for the UAS industry because of how quickly the industry moves. When a new development in UAS is created, open source GIS can respond almost immediately. Whereas, proprietary brands will need to formalize resources and direction on a topic before moving on it. Because direct profits are at stake, it is less likely the proprietary brands will beat open source software to the end goal. However, direction does in some ways help proprietary brands. For the specific functions that ESRI does well, it is very reliable and effective. This can be because there is more available resources generally to tackle specific problems. ESRI is also more user friendly because proprietary development cares significantly about the usability of the platform. Open source cares more about the capability to perform tasks, not how easy it is to perform a task. This is especially as issue for open source because there is also a less central authority to receive help on any particular problem.
Model/Discussion
Steps to create hill-shaded DSM in QGIS:- Load in an appropriate plugin (I believe color ramp manager was used in class)
- data layer added
- Right click DEM, click layer properties
- Enter the styles tab, select a color ramp
- match lowest and highest elevation of DEM in min and max values if you want more linear change in color
- go to raster -> analysis -> DEM
- Generate the DEM with a hillshade effect
- Adjust features and transparency until a fine looking hillshade is overlapped with a DSM
The created aesthetically very similar to the one generated during the proprietary GIS assignment, however it required interaction with more menus. In total, there were more options that could be changed, and an experienced user of GIS would likely be able to interact with those options to generate very high quality results. However, it is nowhere near as simple as ArcMap's process.
The false color image at the top of this post was generated next. It is generated from a rededge sensor on an unmanned aircraft.
The following steps were used to create the image:
- the multispectral rasters were opened as individual layers
- the raster layers were stacked to form a single multiband raster
- band combinations were altered to form a false color infrared image ( 1 - NIR, 2 - Red, 3 - Green)
- The image was exported to the map creator functions
- all other features were added including watermark, band information, scale bar, etc.
Conclusions
Draw upon the previous lab and compare your experience between Arc Desktop and QGIS.- While both programs, at first glance, do not seem very distinct, there are clear differences. ArcMap, to me as a novice, is simply easier to use and is more manageable when trying to understand the best way to accomplish a task. The map making functions specifically are vastly superior to QGIS. Largely, this is because more resources are devoted towards user experience in an proprietary product. Despite the favoritism I have towards the proprietary software, I can see how the increased quantity of uses for QGIS would be advantageous. If I was more experienced at this time in GIS, I think I would be more fond of QGIS. In fact, I may find the proprietary software somewhat limiting or a nuisance if I ever became a QGIS expert.
Draw upon the lab examples, and some of the plug ins you were shown to link how this could relate to UAS data, and perhaps even your final project.
- I think the majority of the examples show, and the plug ins mentioned, would be advantageous to UAS and in general my final project. A few were mentioned regarding remote sensing, that may be useful. However, I do not believe this specific program will be used to handle the bulk of the remote sensing workload, but it could be useful for data visualization. Instead, I think the primary advantage is the base program of QGIS. Ultimately, I do not know what packages I will use, but they are all available, for free. I can see an assortment of problems arising spatially for this capstone, and having a plethora of plugins available will help elevate much of the potential headache.
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