I know I have not done enough research and reading for myself, but I am busy and tired. 🙂
I have finally left my base antenna behind and am now using only the Trimble 5800 with a connection to CORS. Using Carlson SurvCE in the DC.
Trying to work on MI State plane central, but the raw data always has to be translated "N88.30E 38.7 feet" to match NGS monuments. Am I missing something in my setup?? I think so:-S
Just a quick thought Michigan cors when I used it in 2007-2008 was U.S. Survey foot seems like when I had problems it was the difference between US survey foot and international feet. i don't remember the exact numbers but seems like 25' and 12 feet stick in my mind
Make sure your project is using International Feet.
Do other states use international feet?
OR uses iFT
> Do other states use international feet?
Oregon is one.
Arizona
States using International foot plus conversion factors
By my count eight states use the international survey foot. They are: OR, MT, ND, UT, AZ, AR, MI and SC. See map on page 25 of 68 of PDF file: http://geodesyattamucc.pbworks.com/w/file/fetch/63366627/Lec5_2013_SPCS_lecture.pdf
FWIW, to convert meters to US Survey feet multiply by 3937/1200. To convert meters to intenational feet note that 2.54 centimeters equals one inch therefore one meter equals 3.048 international feet (exactly).
States using International foot plus conversion factors
GeeOddMike's list is correct with the exception of Utah - they rescinded the International Foot and adopted the U.S. Survey Foot - see Federal Register Notice, July 16, 2998, Vol 74, No. 47 pgs 34557-34558
States using International foot plus conversion factors
Good stuff!
States using International foot plus conversion factors
It was against my better judgment, so don't blame me! International conversion is the proper way to go IMHO. Too many surveyors think that the USft was invented for/by surveyors and just couldn't let it go the way of the NAD27 dodo. That shiny USft radio button on the software wins out over the Ift button most every time. The Ift/USft confusion has caused a lot of errors for those who aren't paying close attention.
When the request first came from USGS, we couldn't get a consensus on which way to go, so initially, we just imposed the meter as the standard and, if you chose to convert from there, to publish which conversion you were using.
Second round, the Ift supporters weren't invited to the table, so we're stuck with USft. There are still published systems out there in Utah which continue to use the Ift, so you still have to watch out every time with every system.
Maybe we should have just stuck with chains. :'(
JBS
States using International foot plus conversion factors
ARkansas is U.S. Survey foot.
DDSM
States using International foot plus conversion factors
I keep Utah in the 'broken foot' column just so I remember to stay on my toes. Don't forget the Salt Lake Foot as well...
well, you started a discussion about international vs. US survey feet, but unless your easting is wayyyyy larger than your northing I can't see that as the issue
Michigan central false northing is 0. False easting is 6 million meters...
wow!! there you go, that might just work.
States using International foot plus conversion factors
Thanks for the help, but you left out a step:
3.048 feet = 1 meter
1 meter = 1/3.048 = 3.28083989501 International Feet
States using International foot plus conversion factors
I think the conversion is 1 ift = 0.3048m or 1m = 3.280839895 ift
Thanks for all the help! You nailed it!
The DC I used with my old equipment defaulted to international feet, so I never gave it a thought. But the new DC was on US Survey feet.
Converted my Lat/Long to International feet and now I am hitting the NGS monuments dead on.
😀 😀 😀 I so happy!
Thanks again.
States using International foot plus conversion factors
Mea culpa.
1. By definition one inch = 2.54 cm
2. Since twelve inches = one foot, 12 * 2.54 cm = 30.48 cm
3. Convert centimeters to meters by dividing by 100 (100 cm = 1 m) 30.48/100 = 0.3048 m.
4. Since we want to know how many International feet are in a meter we take the reciprocal 1 / 0.3048 = 3.280 839 895 013 123 (to fifteen decimal places).
5. The US Survey foot is defined by 3937 /1200 = 3.280 833 333 333 333 (to the same precision)
BTW, the US Metric Law of 1866 specified that one meter is equal to 39.37 inches exactly. Taken from an article by Mark E. Meade in POB magazine (1 Oct 2007). See also the NGS FAQ at http://www.ngs.noaa.gov/faq.shtml#Feet
Oh yeah, in a million feet the difference is two feet.