Holy Cow, post: 359118, member: 50 wrote: Water, water, everywhere and not a drop to drink!
My money says there is a Pub within walkin distance
Enjoyed the pics
I'm always interested in different perspectives on surveying. Thank you for sharing Victor.
Victor.Plymouth, post: 358912, member: 11292 wrote: Scanning a hulk (an abandoned 'wreck') and a pre-1913 cut Benchmark
What format are the geographical coordinates in on the Benchmark/Wreck picture?
So, welcome. Spent a few years working out of an office above a Hydrographic surveyors in Cork up by the airport. Worked with them landside as well as the only other current Irish Hydro crowd in Crosshaven. Crosshaven guys also did our Trimble servicing for a while.
More than likely I know a few guys you worked with. Not in Cork currently but rather the Western Australian desert hot bit building a rather large thing.
Cheers.
Stephen Johnson, post: 359297, member: 53 wrote: What format are the geographical coordinates in on the Benchmark/Wreck picture?
Hello Stephen,
They are metric grid coordinates that are designed to cover the island which includes England, Wales and Scotland. The True Origin is the 2o West Meridian and 49o North, utilising a Transverse Mercator projection. The offsets to the north and west put the False Origin to the SW of this island and Plymouth, Devon lies about 250km east of this False Origin (hence, in the picture, 250,253 mE) and about 53km north of the False Origin (hence, 53,023 mN).
As an exercise, I sometimes ask students to compute a metric distance in the Imperial (!) foot and the US survey foot. Is the US Survey foot used today and used across the whole of the USA or do you have State variants?
If anyone else is reading this, are there other units around the world in common use today?
Paul The Irishman, post: 359358, member: 262 wrote: So, welcome. Spent a few years working out of an office above a Hydrographic surveyors in Cork up by the airport. Worked with them landside as well as the only other current Irish Hydro crowd in Crosshaven. Crosshaven guys also did our Trimble servicing for a while.
More than likely I know a few guys you worked with. Not in Cork currently but rather the Western Australian desert hot bit building a rather large thing.
Cheers.
Hello Paul ... you'll have a better tan than you would have got in Cork!
Yes, I worked in that building from when it was new (and its predecessor in Grange). I visited Jim and Tommy (Irish Hydrodata) only last year. When IHD was started, we gathered the data for the first Irish home-produced chart and the original was presented to the Taoiseach. All so changed now with Ireland's fantastic Marine Institute and Geological Survey of Ireland.
Yes I know Barry (and Mike, who left) at Crosshaven. They had been at the office in Grange when I first started there in 1978. There was a land surveying company at Crosshaven too.
Victor.Plymouth, post: 359506, member: 11292 wrote: If anyone else is reading this, are there other units around the world in common use today?
I perform all my surveys in "Smoots" 😀
Since the difference between International Foot and US Survey Foot is exactly 2 ppm, it is moot for most practical work except when using large grid coordinates. Most states in the US have legislation selecting one or the other for their State Plane Coordinate system, but there is no consensus among them. A few states perhaps leave it to the user, who then needs to be very sure to put the selection in their metadata.
Victor.Plymouth, post: 359506, member: 11292 wrote: Hello Stephen,
They are metric grid coordinates that are designed to cover the island which includes England, Wales and Scotland. The True Origin is the 2o West Meridian and 49o North, utilising a Transverse Mercator projection. The offsets to the north and west put the False Origin to the SW of this island and Plymouth, Devon lies about 250km east of this False Origin (hence, in the picture, 250,253 mE) and about 53km north of the False Origin (hence, 53,023 mN).As an exercise, I sometimes ask students to compute a metric distance in the Imperial (!) foot and the US survey foot. Is the US Survey foot used today and used across the whole of the USA or do you have State variants?
If anyone else is reading this, are there other units around the world in common use today?
The Survey foot is used in the majority of the US. for some strange reason Arizona insists on using the International Foot and North Dakota uses the International foot for coordinates based on NAD83/WGS 84 while still using the Survey foot on those still using NAD27 and still using the survey foot for actual distances on the ground.
Thank you, gentlemen (any ladies on here?).
You may know that the GPS/ GRS80 model of the Earth has 0 degrees longitude some 100 metres from the original Greenwich (Greenwich, London, England) Meridian. This arbitrary line, through the telescope at the Royal Observatory, was used as a reference for other astronomical longitudes.
In setting the GRS80 model, was there a longitude made equal to an astronomical longitude, and what is it? ... And the latitude? Is that a significant place in the USA, such as a survey monument?
Vic
Victor.Plymouth, post: 359506, member: 11292 wrote: Hello Stephen,
They are metric grid coordinates that are designed to cover the island which includes England, Wales and Scotland. The True Origin is the 2o West Meridian and 49o North, utilising a Transverse Mercator projection. The offsets to the north and west put the False Origin to the SW of this island and Plymouth, Devon lies about 250km east of this False Origin (hence, in the picture, 250,253 mE) and about 53km north of the False Origin (hence, 53,023 mN).As an exercise, I sometimes ask students to compute a metric distance in the Imperial (!) foot and the US survey foot. Is the US Survey foot used today and used across the whole of the USA or do you have State variants?
If anyone else is reading this, are there other units around the world in common use today?
The vara is still required for field notes filed at the General Land Office in Texas. Standardized at 33-1/3 inches by John Borden in 1837 when he became the first land commissioner.
Victor.Plymouth, post: 358795, member: 11292 wrote: Hi, everyone. Thanks for your greetings.
I've been following via Twitter for some time as the land surveying commentaries are very useful insights for my students.
I'll post some pictures of our surveys in Plymouth (southwest UK). I started on wharf surveys on the River Thames in 1976, Richard.
I worked out of Cork, Totalsurv, 1977 to 1987. Just discussing vessel dimensional control surveys with my colleagues today. We do all three of taping, Total Station and laser scanning. Whole lot of issues with precision v. scale, multiple reference frames, it's place in debates on positioning accuracy/ accuracy at the outer beams in Multibeam surveys/ the role of the patch test.
More in a minute
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I have a surveying brother-in-law Piers Street (Sussex Surveyors) around the corner from you.
Cheers,
Derek
I've seen square Spanish leagues in 19th century Deed descriptions. A Spanish league is 5000 varas.
Here are some units of measure from Brown's Boundary Control and Legal Principles, Fourth Edition:
