After a while, all the ponds and mossy outcrops look the same. Our fearless field party got lost under my direction. Without a doubt, the Boundary Waters is the most lovely mosquito and wood tick hatchery in the lower 48. Recently, I was doing field work in the Boundary Waters area of northern Minnesota. Of course, I continue to be amazed with the power of Google Earth… I have written previous blogs about the amazing and free MapWindow and also the very powerful Manifold GIS system. Most software is essentially a trimmed down and specialized version of ArcGIS, tailored toward a specific industry. So why go with someone else? Try cost, ease of use, memory drain, and the fighting spirit to stick it to the man. prj is valuable if you have an assigned projection.) I should also chime in that ESRI continues to dominate the GIS market because they do make amazing products. So when you collect your data, make sure you can output as standard shape files, composed of the minimum triad of. However, the ESRI shape-file format with the multitude of files is the standard for most industries and academia. Moral of the lesson: just because the file format is on the software list, doesn’t mean it will work. He went back and trimmed the original image in SOLO Office and everything worked smooth. It ended up that he used an ArcGIS product to trim the image and for some reason, the new image could not be read in a non-ESRI GIS. We thought the problem was that the file was too big (~30 MB), but that wasn’t the case. However, every time he loaded the map, the program would crash. Both the original and trimmed map were saved in the standard geotiff (.tif) format which is read by SOLO Field. His background map was a trimmed image from a much larger air photo. Todd wanted to use SOLO Field on a Nomad Computer for collecting GIS data. docx yet? I recently worked on an interesting problem with a colleague of mine that was a model for subtlety. Have you ever been frustrated because you thought you were using a standard file format and the program would not read the file? For starters, have you received a. My advice: if you are not sure, save your data as a text (.txt) or comma-separated values (.csv) format. While ESRI shape files (explained in another blog) are the most commonly shared, not all GIS programs allow for shape files. Rather than regurgitate a litany of acronyms, let’s just assume any product you use will have its own file format. In a similar circumstance, it seems that every GIS program uses its own proprietary format. In fairness, both Garmin and Magellan produce excellent products and more and more third party software can allow for Garmin and Magellan input. In summary, make sure your software can read NMEA format. However, to keep customer’s cash, Garmin and Magellan use mapping software that relies on proprietary transmitted information so you cannot use other mapping software and you cannot use other brands of receivers. The most common commercial GPS receivers are produced by Garmin and Magellan. Because it is a simple ASCII line, it is easy to write software that seeks out this transmitted line and parses out the needed information. This line transmits the time, latitude, longitude, quality of fix, number of satellites, horizontal dilution of precision, altitude, and some other information. Most important is the summary line, or ‘fix data’ line, known as the GGA line. The government-funded GPS satellite cluster is normally interpreted in a standardized, public format established by the US Coast Guard called “NMEA.” The GPS receiver will read the satellite information and transmit NMEA lines as ASCII strings. The simplest solution is to limit products that only save data in proprietary formats. The success, therefore, is learning to minimize proprietary formats. That is, while some software seems “universal,” the truth is that files produced in one version are not compatible in a competing version. Most of the questions I receive about map making have to do with proprietary software.
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