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RazorbackFan

Cast Away Benchmarks

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After watching the movie Cast Away for about the 20th time on TNT tonight, I wondered where the last scene of the movie was filmed. I was able to pause the movie in a few spots and got the cross road information (FM 1268 & FM 48) off of the signs. Of course, had I just googled it I would have found it much quicker, but wheres the fun in that? Anyhow, after finding the spot I then pondered: "I wonder if there are any benchmarks nearby?". I pulled up Scaredy Cat's site. Sure enough there are 3 at that very intersection!

 

However, 2 of the entries appear to be duplicates. The same mark "F 457 RESET" seems to have 2 PIDs: FL0090 & FL1906.

 

Pull up FL0090 and you see it was set by the Atchison Topeka & Santa Fe Railroad in 1950. Scroll to the bottom of the datasheet and you'll see that it has an error code of F (Bench Mark not yet adjusted) for the elevation. The original mark (FL0089) was set by the CGS in 1937 and reported as destroyed by the Texas Highway Department in February of 1951 (a year after the RESET mark was placed).

 

The datasheet for FL1906 was written by the Coast & Geodetic Survey in 1951. I'm presuming they came back to blue book the reset mark? This location of this mark is listed as "NO CHECK". Something I haven't seen before. Yet, the postion given is very precise (the seconds go out to 6 decimal places).

 

The mark was re-visited by the USGS in 1966. They logged the find under the FL0090 PID. I'm guessing FL1906 should probably be removed as a duplicate and FL0090 should have the error code of F removed from it. If I ever wind up in that part of the country I'll have to give these marks a try and visit the nearby Arrington Ranch (also featured in the movie)!

 

-RF

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This is one of those cases where the same physical mark F 547 RESET has two identities and hence two PIDs:

1 ) a vertical control mark (established 1950 by ATSFRR) FL0090

2 ) a horizontal control mark (established 1951 by CGS) FL1906

 

Both are third order and both have some note about not being checked. The dsdata.txt reference doesn't seem to explain much about "NO CHECK" - it isn't even listed as one of the options on the coordinates line.

 

The 6-figure seconds values listed for the horizontal control mark's horizontal coordinates is not its actual precision as physically measured but instead the (nominal precision) output of the adjustment program for this mark.

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After watching the movie Cast Away for about the 20th time on TNT tonight, I wondered where the last scene of the movie was filmed. I was able to pause the movie in a few spots and got the cross road information (FM 1268 & FM 48) off of the signs. Of course, had I just googled it I would have found it much quicker, but wheres the fun in that?

LOL! I did something similar once. I happened upon the movie "Radio Flyer" (hey, Tom Hanks was in that one, too!) on TV once, right during a scene at a small airport that was obviously somewhere in California's Gold Country. So next thing you know, there I am with Jeppeson maps strewn over the living room carpet, trying to find an airport in the Sierra foothills that has runways labeled "17" and "35."

 

It turned out to be Columbia airport, near Sonora. Here's its entry on the California Film Commission's website:

 

http://ca.reel-scout.com/loc_detail.aspx?id=1381

 

It's right near Columbia State Historic Park, a preserved Gold Rush ghost town. Fun place to visit if you're ever in the area, such as if you're headed to Yosemite. I have friends who live not far from there, and I've gotten my friend Bob interested in benchmark hunting, so maybe we'll go over and see what we can find someday. I see there's also a mark right near the parking lot for the old town, but judging from a 2006 photo on Geocaching.com, it's nearly buried in poison oak. :blink: Thanks, but no thanks...

 

Patty

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I'll take a look at this and let you know what gets resolved. We have had several of these brought to our attention by geocachers -- Thanks. These errors stem from the fact that when NGS created the original databases, there were separate horizontal and vertical systems. They were later merged into what we now call the NGS Integrated Database and in that process there was several "burps" like these. We appreciate the efforts by the public to help us make this system come as close to perfect as is humanly possible.

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I have reviewed these data and forwarded a correction notice to the NGS database team to combine the data and remove one of the PIDs. To Black Dog and others, the term "NO CHECK" refers to the fact that the horizontal position for this point was determined by what surveyors call a spur traverse of just one direction and distance from the nearby triangulation station HILL (FL1908). While the direction and distance from a known point are sufficient to compute a position, they do not provide an independent check on that value and redundant measurements are at the heart of geodetic surveying to ensure positional integrity. When such a situation occurs the resulting position or height is called NO CHECK.

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"After watching the movie Cast Away for about the 20th time on TNT tonight, I wondered where the last scene of the movie was filmed. I was able to pause the movie in a few spots and got the cross road information (FM 1268 & FM 48) off of the signs."

 

 

That's actually a Waymarked site, in a category which has something to do with places that movie scenes were shot. If you can get to it on Waymarking.com, you can log your visit. [Grin.]

 

-Paul-

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The duplication of PIDs for station F 57 RESET (FL0090 and FL1906) has been corrected. The horizontal and vertical data has all been combined on FL0090 and FL1906 has been removed from NSRS. Thanks for bringing this to our attention, we greatly appreciate the efforts to improve the quality of the data we provide.

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The duplication of PIDs for station F 57 RESET (FL0090 and FL1906) has been corrected. The horizontal and vertical data has all been combined on FL0090 and FL1906 has been removed from NSRS. Thanks for bringing this to our attention, we greatly appreciate the efforts to improve the quality of the data we provide.

 

Dave does this involve all duplicated PID's that have been reset?

I have several resets that have the Original Data sheet and the Reset Data Sheet.

Many are at a little different location,changed coordinates Is what I mean.

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This applies just to the two PIDs I mentioned. If you have some others please let me know.

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This applies just to the two PIDs I mentioned. If you have some others please let me know.

I may as well chime in here. I have two stations which I believe are the same station:

 

They are in Brooklyn NY:

KU3532 "PROSPECT WATER TOWER 1903"

 

KU1297 "22"

 

The first is a monument which stands at the position of the old water tower which was used in the Triangulation of New York City in 1903 - 1905. It is a horizontal control station which is a copper bolt mounted on a granite monument.

 

The second is a bench mark surveyed in 1952 and which used the same monument.

 

Presumably the leveling party did not realize the monument was already in the NGS databasen or perhaps the clerk in the office who cataloged their report failed to notice this fact. Since the bench mark has scaled coordinates, the coordinates do not match, but the description is unmistakable and there certainly are not two of these granite monuments with copper bolts in the area.

Edited by Papa-Bear-NYC

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Station GF0567,GF0568,GF0899,GF0901,GG0039. and GG0951, are not duplicate PIDs these are all different marks and will treated as such. Stations KU1297 and KU3532 however are arguably the same, but may present a problem because of how the observational data is treated in the NGS database. I will work with the DB team to see how this should be handled.

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Station GF0567,GF0568,GF0899,GF0901,GG0039. and GG0951, are not duplicate PIDs these are all different marks and will treated as such. Stations KU1297 and KU3532 however are arguably the same, but may present a problem because of how the observational data is treated in the NGS database. I will work with the DB team to see how this should be handled.

Thanks Dave. You're the best.

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Station GF0567,GF0568,GF0899,GF0901,GG0039. and GG0951 are not duplicate PIDs these are all different marks and will treated as such

 

I will mark them as such.

 

Thank you Dave.

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Here is a pair of PIDs for the same disk. On 1 datasheet the elevation is "POSTED" and on the other the elevation is "ADJUSTED".

 

1 LRC HO0381 "Adjusted elevation"

 

1 LRC HO0645 "Posted elevation"

 

The descriptions took us to the same disk.

 

What is "POSTED" elevation?

 

John

 

No one knows what "POSTED" elevation is versus "ADJUSTED"?

 

Shirley~

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Yes they are. I have already forwarded a request to the NGS database team to make the correction.

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