Thanks for the timely correction. Very cool if true...I'm surprised that this isn't general knowledge seeing that it would save a person several thousand dollars per unit.
On Monday 17 July 2006 13:41, you wrote: > From: Michael Sears <[EMAIL PROTECTED]> > Subject: Re: GPS units and accuracy data > > (snip) > First, there is NO way to post correct data collected from > a Garmin or Magellan unit. You are stuck with the data that you have > collected. > (endsnip) > ----------------------------------------------- > > I'm afraid that I must respectfully disagree with you. Others do as well. > > Professor Antonio Tabernero Galán was the pioneer in the subject. Although > his work was not the first to extract raw data from a Garmin GPS unit, it > was the first to create software that was useable in the field and in the > office. See http://artico.lma.fi.upm.es/numerico/miembros/antonio/async/ > > Doctor Dennis Milbert, head geodecist, National Geodetic Survey (NGS) has > also produced some very nice software, including a variety for post- > processing both static and kinematic data from Garmin units. He was also > kind enough to work with me a few years back to modify one of his softs to > use Garmin's newer line of remote sensors. I'm referring to the GPS-16, - > 17, -18 and so on. > > Once Dr. Milbert's software converts the Garmin raw data into a RINEX > file, it is also useable in many (any?) of the current packages that post- > process using RINEX and SP3 files in combination. I have attempted this in > a few of them, but cannot make a claim that it will work in all. > > Professor Galán's software is well documented, and it is able to get much, > much better results than the NMEA output alone. Other people have used it > more than I, and I won't get into great detail over something that I'm not > extremely familiar with. > > These are cases of hobbyist work gone into overdrive by mathematicians > obsessed with an idea. This is how some of the best technical innovations > in our history have come about. There are also a few commercial > applications out there as well that use handheld, single frequency raw > output to post-process data and receive results in the sub-meter range. > See GRINGO and PostPro for a couple of examples. > > I currently use DeLorme's Blue Logger to collect raw SiRF data which is > able to be processed with DeLorme's PostPro. They claim sub-meter static > and sub-5 meter kinematic. That is legalese, of course, and I've not had > data get close to the worst-case scenario unless I was in very deep cover > or the useable satellite count was at 5 or 4. My best results have been to > use PostPro to convert the raw SiRF data to a RINEX file and then use Dr. > Milbert's software to convert the RINEX data to a position file. Your > mileage may vary. > > Respectfully, > Frank Looper, Jr. *SLA > > > > *Semi-literate amateur. -- Michael W. Sears, Ph.D. Associate Editor, Herpetologica Assistant Professor Center for Ecology Department of Zoology Southern Illinois University Carbondale, IL 62901 phone: 618-453-4137 web: http://equinox.unr.edu/homepage/msears http://www.ecology.siu.edu "Natural selection is a mechanism for generating an exceedingly high degree of improbability" Sir Ronald A. Fisher (1890-1962)
