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Z15

New Datasheets

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Found this notice...

 

Thursday, September 13, 2007

 

Programming Glitch Gives Public a Sneak Peek at New NGS Data Sheet

 

In the process of running tests on the new accuracy loading and data sheet retrieval programs, the new data sheets became available to the public prematurely. In addition, the data sheets were generated from a test version of the NGSIDB.

 

The data that were published were correct and accurate; however it may not have been complete. Depending on the area from where data were retrieved, the new positions may not have been loaded and an old position would have appeared on the data sheet. Another problem for the user may have resulted from the change in the format which could have affected processing the data sheets in an automated fashion.

 

This problem affected data sheets retrieved from approximately 1:30 p.m. EDT Wednesday, September 12 through 11:00 a.m. EDT Thursday, September 13. The problem has been partially corrected by putting the old data sheet program back into production.

 

Due to the interdependency between the new accuracy loading process, new database tables and the related redesign of the data sheet program, NGS has suspended loading the new positions and accuracy data into the NGSIDB until known problems can be resolved.

 

At this time only data for Alaska, Alabama, Arkansas, Arizona, California, Maine, and New Hampshire have been loaded. All the data are correct and accurate.

 

NGS will review the options on how to proceed and will issue a follow up announcement. Also, NGS will make a formal announcement when the new data sheets are officially available to the public.

 

We apologize for any inconvenience to our users and ask that you direct all questions to the NGS Information Center, (301) 713-3242, ngs.infocenter@noaa.gov.

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Here's the first part of what one of the new NSRS2007 Datasheets looks like with the absolute accuracy estimates:

 

AE2999 ***********************************************************************
AE2999  CBN		 -  This is a Cooperative Base Network Control Station.
AE2999  DESIGNATION -  OLD MAIN
AE2999  PID		 -  AE2999
AE2999  STATE/COUNTY-  AR/WASHINGTON
AE2999  USGS QUAD   -  FAYETTEVILLE (1995)
AE2999
AE2999						 *CURRENT SURVEY CONTROL
AE2999  ___________________________________________________________________
AE2999* NAD 83(NSRS2007)-  36 04 05.11033(N) 094 10 11.98402(W)	ADJUSTED  
AE2999* NAVD 88		 -	   433.9	(meters) 1424.	(feet)  GPS OBS   
AE2999  ___________________________________________________________________
AE2999  X		   -	-375,351.031 (meters)					 COMP
AE2999  Y		   -  -5,148,217.555 (meters)					 COMP
AE2999  Z		   -   3,734,539.992 (meters)					 COMP
AE2999  LAPLACE CORR-		   1.03  (seconds)					DEFLEC99
AE2999  ELLIP HEIGHT-		 405.911 (meters)		  (02/10/07) GPS OBS
AE2999  GEOID HEIGHT-		 -28.01  (meters)					 GEOID03
AE2999
AE2999  ------- Accuracy Estimates (at 95% Confidence Level in cm) --------
AE2999  Type	PID	Designation					  North   East  Ellip
AE2999  -------------------------------------------------------------------
AE2999  NETWORK AE2999 OLD MAIN						  0.88   0.71   2.59
AE2999  -------------------------------------------------------------------
AE2999  LOCAL   FG1941 CLARPORT						  1.04   0.80   3.04
AE2999  LOCAL   GF1020 HOMEPORT						  1.12   0.90   3.33
AE2999  LOCAL   FG1957 OZARPORT						  0.90   0.73   2.65
AE2999  LOCAL   GF1026 ARP 2							 1.12   0.90   3.29
AE2999  LOCAL   FH1262 POCOLA							1.08   0.84   3.14
AE2999  LOCAL   AE2989 AGRONOMY						  1.14   0.92   3.37
AE2999  LOCAL   AE2997 ENGINEERING EXPERIMENT STATION	1.16   0.90   3.39
AE2999  LOCAL   AE3011 W H PHILLIPS					  1.00   0.78   2.94
AE2999  -------------------------------------------------------------------
AE2999  LOCAL   AVERAGE								  1.07   0.85   3.14

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I also found one in my area by chance..

 

[size=1]DATABASE = Sybase ,PROGRAM = datasheet, VERSION = 7.50
1		National Geodetic Survey,   Retrieval Date = SEPTEMBER 15, 2007
RL0593 ***********************************************************************
RL0593  CBN		 -  This is a Cooperative Base Network Control Station.
RL0593  DESIGNATION -  E 151
RL0593  PID		 -  RL0593
RL0593  STATE/COUNTY-  MI/HOUGHTON
RL0593  USGS QUAD   -  PELKIE (1985)
RL0593
RL0593						 *CURRENT SURVEY CONTROL
RL0593  ___________________________________________________________________
RL0593* NAD 83(NSRS2007)-  46 45 53.91064(N) 088 42 56.16824(W)	ADJUSTED  
RL0593* NAVD 88		 -	   242.170  (meters)  794.52  (feet)  ADJUSTED  
RL0593  ___________________________________________________________________
RL0593  X		   -	  98,108.669 (meters)					 COMP
RL0593  Y		   -  -4,375,802.741 (meters)					 COMP
RL0593  Z		   -   4,624,058.897 (meters)					 COMP
RL0593  LAPLACE CORR-		  -9.87  (seconds)					DEFLEC99
RL0593  ELLIP HEIGHT-		 208.731 (meters)		  (02/10/07) GPS OBS
RL0593  GEOID HEIGHT-		 -33.46  (meters)					 GEOID03
RL0593  DYNAMIC HT  -		 242.185 (meters)	 794.57  (feet)  COMP
RL0593
RL0593  ------- Accuracy Estimates (at 95% Confidence Level in cm) --------
RL0593  Type	PID	Designation					  North   East  Ellip
RL0593  -------------------------------------------------------------------
RL0593  NETWORK RL0593 E 151							 0.61   0.45   1.78
RL0593  -------------------------------------------------------------------
RL0593  LOCAL   RL0476 TT 10 C						   2.20   1.41   7.10
RL0593  LOCAL   RL1503 P 324							 2.12   1.41   7.21
RL0593  LOCAL   QL0101 ISABELLA						  0.78   0.57   2.35
RL0593  LOCAL   PL0300 L 88							  0.84   0.59   2.43
RL0593  LOCAL   PL0361 T 312							 0.71   0.51   1.82
RL0593  LOCAL   RK0039 G 46							  0.76   0.55   2.29
RL0593  LOCAL   RK0097 T 46							  0.76   0.55   2.27
RL0593  LOCAL   RK0448 U 329							 0.76   0.53   2.27
RL0593  LOCAL   RK0194 L 61							  0.73   0.59   2.33
RL0593  LOCAL   QK0547 908 7096 TIE					  0.73   0.53   2.16
RL0593  LOCAL   RK0378 LSC 7 B 31						0.78   0.55   2.33
RL0593  LOCAL   AA8080 FIRE HALL						 0.78   0.57   2.31
RL0593  LOCAL   AA8081 IRON							  0.78   0.57   2.31
RL0593  LOCAL   AF9491 CHEBOYGAN 1 CORS ARP			  0.61   0.45   1.78
RL0593  LOCAL   AF9501 DETROIT 1 CORS ARP				0.61   0.45   1.78
RL0593  LOCAL   AF9510 SAGINAW 1 CORS ARP				0.61   0.45   1.78
RL0593  LOCAL   AF9550 UPPER KEWEENAW 1 CORS ARP		 0.61   0.45   1.78
RL0593  LOCAL   AI2695 PICKFORD CORS ARP				 0.61   0.45   1.78
RL0593  LOCAL   AJ5559 CADILLAC CORS ARP				 0.61   0.45   1.78
RL0593  LOCAL   AJ5561 GAYLORD CORS ARP				  0.61   0.45   1.78
RL0593  LOCAL   AJ5563 ALPENA CORS ARP				   0.61   0.45   1.78
RL0593  LOCAL   AJ5567 L'ANSE CORS ARP				   0.61   0.45   1.78
RL0593  LOCAL   AJ5569 ESCANABA CORS ARP				 0.61   0.45   1.78
RL0593  LOCAL   AJ5571 NEWBERRY CORS ARP				 0.61   0.45   1.78
RL0593  -------------------------------------------------------------------
RL0593  LOCAL   AVERAGE								  0.81   0.58   2.45
RL0593
RL0593  MODELED GRAV-	 980,667.8   (mgal)					   NAVD 88
RL0593
RL0593  VERT ORDER  -  SECOND	CLASS 0
RL0593
RL0593.The horizontal coordinates were established by GPS observations
RL0593.and adjusted by the National Geodetic Survey in February 2007.
RL0593
RL0593.The orthometric height was determined by differential leveling
RL0593.and adjusted by the NATIONAL GEODETIC SURVEY in
RL0593
RL0593.The X, Y, and Z were computed from the position and the ellipsoidal ht.
RL0593
RL0593.The Laplace correction was computed from DEFLEC99 derived deflections.
RL0593
RL0593.The ellipsoidal height was determined by GPS observations
RL0593.and is referenced to NAD 83.
RL0593
RL0593.The geoid height was determined by GEOID03.
RL0593
RL0593.The dynamic height is computed by dividing the NAVD 88
RL0593.geopotential number by the normal gravity value computed on the
RL0593.Geodetic Reference System of 1980 (GRS 80) ellipsoid at 45
RL0593.degrees latitude (g = 980.6199 gals.).
RL0593
RL0593.The modeled gravity was interpolated from observed gravity values.
RL0593
RL0593;					North		 East	 Units Scale Factor Converg.
RL0593;SPC MI N	 -   221,669.513 7,868,965.464   MT  0.99993787   -1 14 24.1
RL0593;SPC MI N	 -   727,262.18 25,816,815.83   iFT  0.99993787   -1 14 24.1
RL0593;UTM  16	  - 5,180,476.269   369,000.692   MT  0.99981093   -1 15 00.3
RL0593
RL0593!			 -  Elev Factor  x  Scale Factor =   Combined Factor
RL0593!SPC MI N	 -   0.99996728  x   0.99993787  =   0.99990515
RL0593!UTM  16	  -   0.99996728  x   0.99981093  =   0.99977822
RL0593
RL0593						  SUPERSEDED SURVEY CONTROL
RL0593
RL0593  ELLIP H (06/11/02)  208.725  (m)					   GP(	   ) 4 1
RL0593  NAD 83(1994)-  46 45 53.91044(N)	088 42 56.16737(W) AD(	   ) B
RL0593  ELLIP H (09/20/95)  208.723  (m)					   GP(	   ) 1 2
RL0593  NAVD 88 (09/20/95)  242.17   (m)		  794.5	(f) LEVELING	3  
RL0593  NGVD 29 (??/??/92)  242.157  (m)		  794.48   (f) ADJ UNCH	2 0
RL0593
RL0593.Superseded values are not recommended for survey control.
RL0593.NGS no longer adjusts projects to the NAD 27 or NGVD 29 datums.
RL0593.See file dsdata.txt to determine how the superseded data were derived.
RL0593
RL0593_U.S. NATIONAL GRID SPATIAL ADDRESS: 16TCS6900180476(NAD 83)
RL0593_MARKER: DB = BENCH MARK DISK
RL0593_SETTING: 7 = SET IN TOP OF CONCRETE MONUMENT
RL0593_SP_SET: SET IN TOP OF CONCRETE MONUMENT
RL0593_STAMPING: E 151 1948
RL0593_MARK LOGO: CGS   
RL0593_MAGNETIC: N = NO MAGNETIC MATERIAL
RL0593_STABILITY: C = MAY HOLD, BUT OF TYPE COMMONLY SUBJECT TO
RL0593+STABILITY: SURFACE MOTION
RL0593_SATELLITE: THE SITE LOCATION WAS REPORTED AS SUITABLE FOR
RL0593+SATELLITE: SATELLITE OBSERVATIONS - July 17, 2001
RL0593
RL0593  HISTORY	 - Date	 Condition		Report By
RL0593  HISTORY	 - 1948	 MONUMENTED	   CGS
RL0593  HISTORY	 - 19940829 GOOD			 NGS
RL0593  HISTORY	 - 19990311 GOOD			 MIDT
RL0593  HISTORY	 - 20010717 GOOD			 MIDT[/size]

Note--rest of ds omiited

Edited by Z15

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Hmmm, I bet this messes up my Perl script for converting these sheets to a smaller readable file for my PALM. Where's the interface document from the NGS on this anyways? That's what we do in the software world. :(

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Oh-oh...

 

RL0593 ***********************************************************************

RL0593 CBN - This is a Cooperative Base Network Control Station.

RL0593 DESIGNATION - E 151

RL0593 PID - RL0593

RL0593 STATE/COUNTY- MI/HOUGHTON

RL0593 USGS QUAD - PELKIE (1985)

RL0593

RL0593 *CURRENT SURVEY CONTROL

RL0593 ___________________________________________________________________

RL0593* NAD 83(1994)- 46 45 53.91044(N) 088 42 56.16737(W) ADJUSTED

RL0593* NAVD 88 - 242.170 (meters) 794.52 (feet) ADJUSTED

RL0593 ___________________________________________________________________

RL0593 X - 98,108.687 (meters) COMP

RL0593 Y - -4,375,802.738 (meters) COMP

RL0593 Z - 4,624,058.884 (meters) COMP

RL0593 LAPLACE CORR- -9.87 (seconds) DEFLEC99

RL0593 ELLIP HEIGHT- 208.72 (meters) GPS OBS

RL0593 GEOID HEIGHT- -33.44 (meters) GEOID99

RL0593 DYNAMIC HT - 242.185 (meters) 794.57 (feet) COMP

RL0593 MODELED GRAV- 980,667.8 (mgal) NAVD 88

RL0593

RL0593 HORZ ORDER - B

RL0593 VERT ORDER - SECOND CLASS 0

RL0593 ELLP ORDER - FIRST CLASS II

RL0593

RL0593.The horizontal coordinates were established by GPS observations

RL0593.and adjusted by the National Geodetic Survey in September 1995.

RL0593

RL0593.The orthometric height was determined by differential leveling

RL0593.and adjusted by the National Geodetic Survey in June 1991.

RL0593

RL0593.The X, Y, and Z were computed from the position and the ellipsoidal ht.

RL0593

RL0593.The Laplace correction was computed from DEFLEC99 derived deflections.

RL0593

RL0593.The ellipsoidal height was determined by GPS observations

RL0593.and is referenced to NAD 83.

RL0593

RL0593.The geoid height was determined by GEOID99.

RL0593

RL0593.The dynamic height is computed by dividing the NAVD 88

RL0593.geopotential number by the normal gravity value computed on the

RL0593.Geodetic Reference System of 1980 (GRS 80) ellipsoid at 45

RL0593.degrees latitude (g = 980.6199 gals.).

RL0593

RL0593.The modeled gravity was interpolated from observed gravity values.

RL0593

RL0593; North East Units Scale Converg.

RL0593;SPC MI N - 221,669.506 7,868,965.482 MT 0.99993787 -1 14 24.1

RL0593;UTM 16 - 5,180,476.263 369,000.710 MT 0.99981093 -1 15 00.3

RL0593

RL0593 SUPERSEDED SURVEY CONTROL

RL0593

RL0593 NGVD 29 - 242.157 (m) 794.48 (f) ADJ UNCH 2 0

RL0593

RL0593.Superseded values are not recommended for survey control.

RL0593.NGS no longer adjusts projects to the NAD 27 or NGVD 29 datums.

RL0593.See file dsdata.txt to determine how the superseded data were derived.

RL0593

RL0593_MARKER: DB = BENCH MARK DISK

RL0593_SETTING: 7 = SET IN TOP OF CONCRETE MONUMENT

RL0593_STAMPING: E 151 1948

RL0593_MAGNETIC: N = NO MAGNETIC MATERIAL

RL0593_STABILITY: C = MAY HOLD, BUT OF TYPE COMMONLY SUBJECT TO

RL0593+STABILITY: SURFACE MOTION

RL0593_SATELLITE: THE SITE LOCATION WAS REPORTED AS SUITABLE FOR

RL0593+SATELLITE: SATELLITE OBSERVATIONS - August 29, 1994

RL0593

RL0593 HISTORY - Date Condition Recov. By

RL0593 HISTORY - 1948 MONUMENTED CGS

RL0593 HISTORY - 19940829 GOOD NGS

RL0593

RL0593 STATION DESCRIPTION

RL0593

RL0593''DESCRIBED BY COAST AND GEODETIC SURVEY 1948

RL0593''2 MI E FROM ALSTON.

RL0593''2.05 MILES EAST ALONG STATE HIGHWAY 35 FROM THE SCHOOL AT ALSTON,

RL0593''ABOUT 1.0 MILE WEST OF THE BRIDGE OVER SILVER RIVER, ABOUT 0.2

RL0593''MILE WEST OF HOUSES ON NORTH AND SOUTH SIDE OF HIGHWAY, ABOUT

RL0593''0.45 MILE WEST OF A ROAD NORTH, AT THE SOUTH END OF A HAY FIELD,

RL0593''73 FEET WEST OF A TELEPHONE POLE, 55 FEET EAST OF A TELEPHONE

RL0593''POLE, 50 FEET NORTH OF THE CENTER LINE OF THE HIGHWAY, 2 FEET

RL0593''SOUTH OF A FENCE LINE, 1 1/2 FEET WEST OF A WHITE WOODEN WITNESS

RL0593''POST, ABOUT LEVEL WITH THE HIGHWAY AND SET IN THE TOP OF A

RL0593''CONCRETE POST PROJECTING 3 INCHES.

RL0593

RL0593 STATION RECOVERY (1994)

RL0593

RL0593''RECOVERY NOTE BY NATIONAL GEODETIC SURVEY 1994 (CFS)

RL0593''STATION IS LOCATED IN QUAD 460884, IN THE SW 1/4 OF SEC 35, T 51 N, R

RL0593''35 W, LAIRD TOWNSHIP, ABOUT 1.0 MI (1.6 KM) EAST FROM ALSTON, 11.0 MI

RL0593''(17.7 KM) WEST OF BARAGA AND ON HIGHWAY RIGHT-OF-WAY PROPERTY. TO

RL0593''REACH FROM THE JUNCTION OF U.S. HIGHWAY 41 AND STATE HIGHWAY 38 IN

RL0593''BARAGA, GO WEST ON HIGHWAY 38 FOR 6.45 MI (10.38 KM) TO A BRIDGE OVER

RL0593''THE STURGEON RIVER. CONTINUE WEST ON HIGHWAY 38 FOR 3.2 MILES (5.1

RL0593''KM) TO A SIDE ROAD LEFT, PRICKET DAM RD, AND THE BARAGA-HOUGHTON

RL0593''COUNTY LINE. CONTINUE WEST ON HIGHWAY 38 FOR 0.95 MI (1.53 KM) TO A

RL0593''BRIDGE OVER THE SILVER RIVER. CONTINUE WEST ON HIGHWAY 38 FOR 1.0 MI

RL0593''(1.6 KM) TO THE STATION ON THE RIGHT AS DESCRIBED. STATION IS FLUSH

RL0593''WITH GROUND. IT IS 142.7 FT (43.5 M) NORTHEAST FROM AND ACROSS THE

RL0593''HIGHWAY FROM A UTILITY POLE, 131.6 FT (40.1 M) NORTHWEST FROM AND

RL0593''ACROSS THE HIGHWAY FROM A UTILITY POLE, 48.2 FT (14.7 M) NORTH FROM

RL0593''THE CENTERLINE OF STATE HIGHWAY 38, 2.0 FT (0.6 M) SOUTH FROM AN

RL0593''EAST-WEST FENCE LINE, 2.0 FT (0.6 M) WEST FROM A METAL WITNESS POST,

RL0593''1.0 FT (0.3 M) SOUTH FROM A CARSONITE WITNESS POST, AND ABOUT 4.0 FT

RL0593''(1.2 M) LOWER THAN THE HIGHWAY.

 

Notice anything different? This one has descriptions. The new one that Z 15 shows us doesn't? Not good....

 

Shirley~

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I'm seeing them in the DC area, too. Here's one example. I don't know PERL but during the transition period it seems you'll need a routine to figure out which format the datasheet is in, then separate routines to parse each flavor accordingly. Have fun!

 

-ArtMan-

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NGS hasn't fully adapted to the new format either....now, if you download a shapefile for a PID that has been updated to NSRS2007, a lot of the fields including Lat Long are messed-up.

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It would be interesting to see an explanation on the NGS website of the accuracy table.

There is a new dsdata.txt file (search for "confidence" in there) but it doesn't have much of an explanation of the values.

 

I am guessing that the columns North and East are the North vector radius and East vector radius of the error ellipse (at the 95% confidence interval size). The long axis radius could be larger than either the North and East values, since the orientation of the ellipse depends on the adjustment results. I am guessing that the Ellip column is the 95% confidence of the elevation value for the mark. (I think the 3 columns are not vectors of an error ellipsoid, but instead 2 vectors of an error ellipse and a completely separate value for the vertical coordinate.)

 

The row called NETWORK is the confidence intervals of the station's absolute error ellipse. The concept of an absolute error ellipse is what relates in concept to us measuring the coordinates of a mark with a GPS receiver. In other words, we are using our GPS receiver to attempt to locate a mark's absolute position with respect to the Earth (the NGS83 datum, actually), and a GPS receiver's error ellipse is the absolute type of error ellipse. The size (like the North or East radius) of a handheld GPS receiver's absolute error ellipse is something like 400 centimeters as opposed to the new datasheets' values around 1 or 2 centimeters.

 

The rows called LOCAL are showing what a surveyor could expect in the accuracy of the distance from the station to another nearby station. It pertains to a particular relative error ellipse between those two stations. We aren't measuring relative accuracy between stations with our GPS receivers.

 

This NGS page discusses the two kinds of error ellipses - absolute and relative.

 

(Yes, I am basically trolling here, hoping that someone from the NGS corrects the above, or someone finds a better NGS website reference that explains the new confidence table in the new datasheets' format.)

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Notice anything different? This one has descriptions. The new one that Z 15 shows us doesn't? Not good....

 

Shirley~

 

I omitted that stuff because there was not change in format.

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It appears local network are stations that were used at the same time as this one was positioned. I was involved in the 2001 survey for the ds I posted. All the CORS stations are MDOT CORS we were working on getting adjusted into the system and the other marks are one that NGS wanted us to use because they were HARN and they wanted to use our survey to improve the positions.

 

My station assignment was L 61 on on the date, each mark was occupied on 3 different days with 2 different sessions on those days and months apart. I think we had 6 months to complete all observations statewide. Many people were involved, mostly 1 per mark but several required 2 men because of the location. If you look at the RK0593, all the marks (exc. CORS) under local had a GPS Surveyor on them at the very same time. All of them are located in the UP of Michigan.

 

We had people from the private sector to other state agencies doing the work.

 

Here are some photos of that day...

L61_MDOT_survey_2001.jpg

L61_1934.jpg

MVC-005F.jpg

MVC-004F.jpg

MVC-012X.jpg

Edited by Z15

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Get a load of the local list on this one. It was used on the same date as L 61. My PS was on this one. It was a dandy to setup on. The were at edge of a breakwall dropping off about 30 ft to Lake Michigan and had to rig it to setup a tripod.

 

 The NGS Data Sheet
See file dsdata.txt for more information about the datasheet.

DATABASE = Sybase ,PROGRAM = datasheet, VERSION = 7.50
1		National Geodetic Survey,   Retrieval Date = SEPTEMBER 16, 2007
QK0547 ***********************************************************************
QK0547  CBN		 -  This is a Cooperative Base Network Control Station.
QK0547  TIDAL BM	-  This is a Tidal Bench Mark.
QK0547  DESIGNATION -  908 7096 TIE
QK0547  PID		 -  QK0547
QK0547  STATE/COUNTY-  MI/SCHOOLCRAFT
QK0547  USGS QUAD   -  HUGHES POINT (1972)
QK0547
QK0547						 *CURRENT SURVEY CONTROL
QK0547  ___________________________________________________________________
QK0547* NAD 83(NSRS2007)-  45 58 11.66055(N) 085 52 18.24801(W)	ADJUSTED  
QK0547* NAVD 88		 -	   178.753  (meters)  586.46  (feet)  ADJUSTED  
QK0547  ___________________________________________________________________
QK0547  X		   -	 319,692.727 (meters)					 COMP
QK0547  Y		   -  -4,429,303.373 (meters)					 COMP
QK0547  Z		   -   4,563,026.591 (meters)					 COMP
QK0547  LAPLACE CORR-		   2.46  (seconds)					DEFLEC99
QK0547  ELLIP HEIGHT-		 143.708 (meters)		  (02/10/07) GPS OBS
QK0547  GEOID HEIGHT-		 -35.06  (meters)					 GEOID03
QK0547  DYNAMIC HT  -		 178.761 (meters)	 586.49  (feet)  COMP
QK0547
QK0547  ------- Accuracy Estimates (at 95% Confidence Level in cm) --------
QK0547  Type	PID	Designation					  North   East  Ellip
QK0547  -------------------------------------------------------------------
QK0547  NETWORK QK0547 908 7096 TIE					  0.43   0.27   1.29
QK0547  -------------------------------------------------------------------
QK0547  LOCAL   MD0041 W 118							 0.57   0.39   1.55
QK0547  LOCAL   MD1335 Q 112							 0.63   0.43   1.76
QK0547  LOCAL   NE0974 77013 AZ MK					   0.67   0.47   2.00
QK0547  LOCAL   PL0256 W 89 RESET						0.73   0.49   2.21
QK0547  LOCAL   PL0300 L 88							  0.73   0.47   2.14
QK0547  LOCAL   PL0361 T 312							 0.55   0.37   1.37
QK0547  LOCAL   OL0372 G 317							 0.78   0.59   2.31
QK0547  LOCAL   PL0315 W 27							  0.76   0.57   2.31
QK0547  LOCAL   NF0205 A 112							 0.69   0.49   2.06
QK0547  LOCAL   OJ0381 W 41							  0.73   0.55   2.00
QK0547  LOCAL   RJ0430 M 196							 0.65   0.45   1.90
QK0547  LOCAL   QJ0169 U 302							 0.65   0.45   2.02
QK0547  LOCAL   RK0194 L 61							  0.61   0.51   2.02
QK0547  LOCAL   OK0220 Q 91							  0.73   0.51   2.25
QK0547  LOCAL   OK0096 H 86							  0.67   0.47   2.04
QK0547  LOCAL   NF0280 S 110							 0.59   0.41   1.82
QK0547  LOCAL   NF0104 W 103							 0.59   0.41   1.80
QK0547  LOCAL   OK0389 E 97							  1.37   1.10   3.74
QK0547  LOCAL   RJ0586 A 293							 0.57   0.37   1.71
QK0547  LOCAL   NF0434 L 166							 0.67   0.47   2.00
QK0547  LOCAL   NE1504 TT 28 S						   0.69   0.47   2.08
QK0547  LOCAL   OJ1005 TUSCOLA						   0.67   0.47   2.02
QK0547  LOCAL   NE1040 S 336							 0.73   0.45   1.98
QK0547  LOCAL   NF1165 P 330							 0.67   0.49   2.02
QK0547  LOCAL   QJ0363 B 183 RESET					   0.73   0.53   2.18
QK0547  LOCAL   OK0711 WHITE CLOUD					   0.69   0.51   2.06
QK0547  LOCAL   AA5052 J 340							 0.73   0.51   2.27
QK0547  LOCAL   AA8064 KINCHELOE CBL 0				   1.27   0.88   3.80
QK0547  LOCAL   AA8074 B 341							 0.73   0.55   2.25
QK0547  LOCAL   AA8078 CARLSON						   0.67   0.45   2.02
QK0547  LOCAL   AA8083 MYERS							 0.67   0.47   2.06
QK0547  LOCAL   AA8084 MILBOCKER						 0.69   0.45   2.02
QK0547  LOCAL   AA8088 Q 343							 0.74   0.55   2.18
QK0547  LOCAL   AA8095 83102							 0.67   0.45   2.00
QK0547  LOCAL   AA8096 60021 01						  0.71   0.47   2.06
QK0547  LOCAL   AF9491 CHEBOYGAN 1 CORS ARP			  0.43   0.29   1.29
QK0547  LOCAL   AF9501 DETROIT 1 CORS ARP				0.43   0.29   1.29
QK0547  LOCAL   AF9510 SAGINAW 1 CORS ARP				0.43   0.29   1.29
QK0547  LOCAL   AF9550 UPPER KEWEENAW 1 CORS ARP		 0.43   0.27   1.29
QK0547  LOCAL   AI2695 PICKFORD CORS ARP				 0.43   0.29   1.29
QK0547  LOCAL   AJ5551 SAGINAW CORS ARP				  0.43   0.29   1.29
QK0547  LOCAL   AJ5553 BRIGHTON CORS ARP				 0.43   0.29   1.29
QK0547  LOCAL   AJ5555 GRAND RAPIDS CORS ARP			 0.43   0.27   1.29
QK0547  LOCAL   AJ5557 AUBURN HILLS CORS ARP			 0.43   0.29   1.29
QK0547  LOCAL   AJ5559 CADILLAC CORS ARP				 0.43   0.27   1.29
QK0547  LOCAL   AJ5561 GAYLORD CORS ARP				  0.43   0.29   1.29
QK0547  LOCAL   AJ5563 ALPENA CORS ARP				   0.43   0.29   1.29
QK0547  LOCAL   AJ5565 KALAMAZOO CORS ARP				0.43   0.27   1.29
QK0547  LOCAL   AJ5567 L'ANSE CORS ARP				   0.43   0.27   1.29
QK0547  LOCAL   AJ5569 ESCANABA CORS ARP				 0.43   0.27   1.29
QK0547  LOCAL   AJ5571 NEWBERRY CORS ARP				 0.43   0.27   1.29
QK0547  LOCAL   AJ5573 JACKSON CORS ARP				  0.43   0.29   1.29
QK0547  -------------------------------------------------------------------
QK0547  LOCAL   AVERAGE								  0.62   0.43   1.85
QK0547
QK0547  MODELED GRAV-	 980,654.9   (mgal)					   NAVD 88
QK0547
QK0547  VERT ORDER  -  FIRST	 CLASS 0
QK0547
QK0547.The horizontal coordinates were established by GPS observations
QK0547.and adjusted by the National Geodetic Survey in February 2007.
QK0547
QK0547.The orthometric height was determined by differential leveling
QK0547.and adjusted by the NATIONAL GEODETIC SURVEY in June 1991.
QK0547
QK0547.This Tidal Bench Mark is designated as VM 13241
QK0547.by the Center for Operational Oceanographic Products and Services.
QK0547
QK0547.The X, Y, and Z were computed from the position and the ellipsoidal ht.
QK0547
QK0547.The Laplace correction was computed from DEFLEC99 derived deflections.
QK0547
QK0547.The ellipsoidal height was determined by GPS observations
QK0547.and is referenced to NAD 83.
QK0547
QK0547.The geoid height was determined by GEOID03.
QK0547
QK0547.The dynamic height is computed by dividing the NAVD 88
QK0547.geopotential number by the normal gravity value computed on the
QK0547.Geodetic Reference System of 1980 (GRS 80) ellipsoid at 45
QK0547.degrees latitude (g = 980.6199 gals.).
QK0547
QK0547.The modeled gravity was interpolated from observed gravity values.
QK0547
QK0547;					North		 East	 Units Scale Factor Converg.
QK0547;SPC MI N	 -   132,502.825 8,087,436.326   MT  0.99991791   +0 48 55.8
QK0547;SPC MI N	 -   434,720.55 26,533,583.75   iFT  0.99991791   +0 48 55.8
QK0547;UTM  16	  - 5,091,322.643   587,411.295   MT  0.99969393   +0 48 40.5
QK0547
QK0547!			 -  Elev Factor  x  Scale Factor =   Combined Factor
QK0547!SPC MI N	 -   0.99997747  x   0.99991791  =   0.99989538
QK0547!UTM  16	  -   0.99997747  x   0.99969393  =   0.99967141
QK0547
QK0547						  SUPERSEDED SURVEY CONTROL
QK0547
QK0547  ELLIP H (06/11/02)  143.702  (m)					   GP(	   ) 4 1
QK0547  NAD 83(1994)-  45 58 11.66077(N)	085 52 18.24734(W) AD(	   ) B
QK0547  ELLIP H (09/20/95)  143.686  (m)					   GP(	   ) 1 2
QK0547  NAVD 88 (09/20/95)  178.75   (m)		  586.4	(f) LEVELING	3  
QK0547
QK0547.Superseded values are not recommended for survey control.
QK0547.NGS no longer adjusts projects to the NAD 27 or NGVD 29 datums.
QK0547.See file dsdata.txt to determine how the superseded data were derived.
QK0547
QK0547_U.S. NATIONAL GRID SPATIAL ADDRESS: 16TER8741191323(NAD 83)
QK0547_MARKER: B = BOLT
QK0547_SETTING: 32 = SET IN A RETAINING WALL OR CONCRETE LEDGE
QK0547_SP_SET: BREAKWALL
QK0547_MAGNETIC: O = OTHER; SEE DESCRIPTION
QK0547_STABILITY: C = MAY HOLD, BUT OF TYPE COMMONLY SUBJECT TO
QK0547+STABILITY: SURFACE MOTION
QK0547_SATELLITE: THE SITE LOCATION WAS REPORTED AS SUITABLE FOR
QK0547+SATELLITE: SATELLITE OBSERVATIONS - July 17, 2001
QK0547
QK0547  HISTORY	 - Date	 Condition		Report By
QK0547  HISTORY	 - 1969	 MONUMENTED	   USLS
QK0547  HISTORY	 - 1975	 GOOD			 NOS
QK0547  HISTORY	 - 19940805 GOOD			 NGS
QK0547  HISTORY	 - 19940909 GOOD			 NOS
QK0547  HISTORY	 - 19950530 GOOD			 USPSQD
QK0547  HISTORY	 - 19950921 GOOD			 NOS
QK0547  HISTORY	 - 20010717 GOOD			 MIDT
QK0547
QK0547						  STATION DESCRIPTION
QK0547
QK0547'DESCRIBED BY NATIONAL OCEAN SERVICE 1975
QK0547'IN PORT INLAND.
QK0547'IN PORT INLAND, ON THE PROPERTY OF INLAND LIME AND STONE COMPANY AT
QK0547'THE NORTH END OF A BOAT SLIP, 10 METERS (30 FT) SE OF THE SE CORNER OF
QK0547'SILL OF THE PUMP HOUSE BUILDING NO. 10, 7.4 METERS (24.2 FT) SE OF THE
QK0547'SE CORNER OF A FENCE AROUND A TRANSFORMER.  THE HIGHEST POINT OF A
QK0547'CROSS ON TOP OF WESTERLY BOLT OF A CLEAT FASTENED TO THE TOP OF A
QK0547'STEEL BREAKWALL.
QK0547
QK0547						  STATION RECOVERY (1994)
QK0547
QK0547'RECOVERY NOTE BY NATIONAL GEODETIC SURVEY 1994 (CFS)
QK0547'STATION IS LOCATED IN QUAD 450854, 13 KM (8.05 MI) EAST-SOUTHEAST OF
QK0547'GULLIVER, IN PORT INLAND, AT THE NORTH END OF A BOAT SLIP, IN THE
QK0547'SOUTHEAST 1/4 OF SECTION 1, T 41 N, R 13 W, MUELLER TOWNSHIP.
QK0547'OWNERSHIP--SPECIALTY MINERALS INCORPORATED, PORT INLAND OPERATIONS,
QK0547'COUNTY ROAD 432, GULLIVER MI 49840, PHONE 906-283-3456.  TO REACH FROM
QK0547'THE INTERSECTION OF U.S.  HIGHWAY 2 AND COUNTY ROUTE 432 IN GULLIVER,
QK0547'GO SOUTHEAST ON ROUTE 432 FOR 8.15 MI (13.12 KM) TO THE OFFICE
QK0547'BUILDING OF SPECIALITY MINERALS INC.  ON THE RIGHT.  CONTINUE SOUTH
QK0547'FOR ABOUT 100 M (328.1 FT) , GOING UNDER RAILROAD OVERPASS, TO A
QK0547'GRAVELED ROAD.  TURN LEFT, EAST FOR ABOUT 100 M, (328.1 FT) THEN TURN
QK0547'RIGHT, SOUTHERLY, TO A GRAVELED PARKING AREA AND THE STATION ON THE
QK0547'RIGHT, IN THE STEEL BREAKWALL.  STATION IS A PUNCH MARK ON THE CENTER
QK0547'OF A CHISELED CROSS IN THE MOST WESTERLY BOLT SECURING A CLEAT IN THE
QK0547'STEEL BREAKWALL.  IT IS 22.9 M (75.1 FT) EAST OF THE WEST END OF A
QK0547'STEEL BREAKWALL WHERE PUMP STATION IS LOCATED WITH THREE PUMPS, 12.9 M
QK0547'(42.3 FT) SOUTH OF THE CENTERLINE OF A GRAVELED ROAD RUNNING BETWEEN
QK0547'BUILDINGS 7 AND 10, 9.1 M (29.9 FT) SOUTHEAST FROM THE SOUTHEAST
QK0547'CORNER OF BUILDING 10 AND 0.3 M (1.0 FT) SOUTH FROM THE NORTH EDGE OF
QK0547'BREAKWALL.  NOTE--CONTACT MR.  DAVID M.  MICKELSON, QUALITY ASSURANCE
QK0547'COORDINATOR OR MR.  JAMES J.  WEBER, OPERATIONS ENGINEER, OF SPECIALTY
QK0547'MINERALS INC.  OFFICE BEFORE ENTERING.  HARD HAT AND SAFETY GLASSES
QK0547'WILL BE PROVIDED BY COMPANY.  GATE AT ENTRANCE IS NOT LOCKED DURING
QK0547'OPERATING HOURS (24 HRS/DAY--MONDAY THROUGH FRIDAY) .  SANDBAGS WILL
QK0547'HAVE TO BE USED AS 3RD LEG OF TRIPOD WILL HAVE TO REST ON A WOODEN
QK0547'WALKWAY, 1.0 M (3.3 FT) BELOW THE BREAKWALL.
QK0547
QK0547						  STATION RECOVERY (1994)
QK0547
QK0547'RECOVERY NOTE BY NATIONAL OCEAN SERVICE 1994 (JRS)
QK0547'IN PORT INLAND, ABOUT 8.4 MILES (13.5 KM) EAST ON COUNTY ROAD 432 FROM
QK0547'THE VILLAGE OF GULLIVER, ON THE PROPERTY OF SPECIALTY MINERALS, INC.,
QK0547'(OLD PORT INLAND LIME AND STONE CO.) , AT THE NORTHWEST CORNER OF THE
QK0547'HARBOR, AT THE NORTH END OF A BOAT SLIP, 10 METERS (32.8 FT) SE OF THE
QK0547'SE CORNER OF SILL OF THE PUMP HOUSE BUILDING NO.  10, 0.60 METERS
QK0547'(1.97 FT) EAST OF THE EAST FACE OF THE FIBERGLASS GAUGE HOUSE.  THE
QK0547'HIGHEST POINT OF A CROSS ON TOP OF WESTERLY BOLT OF A CLEAT FASTENED
QK0547'TO THE TOP OF A STEEL BREAKWALL BULKHEAD CAP.
QK0547
QK0547						  STATION RECOVERY (1995)
QK0547
QK0547'RECOVERY NOTE BY US POWER SQUADRON 1995
QK0547'RECOVERED IN GOOD CONDITION.
QK0547
QK0547						  STATION RECOVERY (1995)
QK0547
QK0547'RECOVERY NOTE BY NATIONAL OCEAN SERVICE 1995 (MJB)
QK0547'IN PORT INLAND, ABOUT 8.4 MILES (13.5 KM) EAST ON COUNTY ROAD 432 FROM
QK0547'THE VILLAGE OF GULLIVER, ON THE PROPERTY OF SPECIALTY MINERALS, INC.,
QK0547'(OLD PORT INLAND LIME AND STONE CO.) , AT THE NORTHWEST CORNER OF THE
QK0547'HARBOR, AT THE NORTH END OF A BOAT SLIP, 10 METERS (32.8 FT) SE OF THE
QK0547'SE CORNER OF SILL OF THE PUMP HOUSE BUILDING NO.  10, 0.60 METERS
QK0547'(1.97 FT) EAST OF THE EAST FACE OF THE FIBERGLASS GAUGE HOUSE.  THE
QK0547'HIGHEST POINT OF A CROSS ON TOP OF WESTERLY BOLT OF A CLEAT FASTENED
QK0547'TO THE TOP OF A STEEL BREAKWALL BULKHEAD CAP.
QK0547
QK0547						  STATION RECOVERY (2001)
QK0547
QK0547'RECOVERY NOTE BY MICHIGAN DEPARTMENT OF TRANSPORTATION 2001 (GEK)
QK0547'STATION IS LOCATED ON THE PROPERTY OF MICHIGAN LIMESTONE OPERATIONS,
QK0547'INC., PERSONAL PROTECTIVE EQUIPMENT, AND ENTRY PERMIT REQUIRED (NOT
QK0547'SUPPLIED BY MLO, INC.). MARK IS DIFFICULT TO OCCUPY W/O SPECIAL
QK0547'EQUIPMENT, DUE TO A 3.5 FT HIGH WELDED STEEL RAILING 0.5 FT N OF THE
QK0547'STA., AND IS ON THE EDGE OF A BREAKWALL DROPPING OFF TO THE WATER.

*** retrieval complete.
Elapsed Time = 00:00:01

Edited by Z15

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Anyone want to explain to us "idiots" what this 'accuracy' and these 'local' things mean? :( Does it have info (like the reference box) that will help us find the mark? (And, more importantly for me, does it contain anything that I will need to include in my NGS-GPX program?)

 

Mike.

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I think there is nothing of value to us benchmark hunters in the new conficence level table.
I agree. Unless I'm missing something (certainly possible), I just see more irrelevant — to us — material to delete before printing it out for field work.

 

Is there anything of value — again, to us — that we're losing? The only thing I've noticed is that the new sheets do not describe marks as "first order" and such, now that the accuracy is being quantified.

 

-ArtMan-

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I think there is nothing of value to us benchmark hunters in the new conficence level table.
I agree. Unless I'm missing something (certainly possible), I just see more irrelevant — to us — material to delete before printing it out for field work.

 

Is there anything of value — again, to us — that we're losing? The only thing I've noticed is that the new sheets do not describe marks as "first order" and such, now that the accuracy is being quantified.

 

-ArtMan-

 

I was thinking the same thing, but hesitated to say anything in case there was some 'obvious' advantage for me/us that I was missing. :(

 

Now if all the 'scaled' marks could somehow become 'corrected'...

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Actually, I did notice a change that anyone using scripts to parse the datasheet - in the original (current?) version, descriptions (find logs) are preceded by an apostrophe. In this new version, it appears to be a quotation mark... :(

 

Me.

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...Now if all the 'scaled' marks could somehow become 'corrected'...
Well, I don't know that it's possible to do that absent a site visit with survey or geodetic-grade gear, but it does seem possible to more accurately derive latitude and longitude of a place on a USGS topo map than produced by the original technique of ruler and pencil (or whatever).

 

Thanks to a PDF extension called GeoPDF, which USGS is supporting, you can get the horizontal coordinates of a mark probably within a couple of tenths of a second accuracy, as opposed to the six seconds advertised for marks with scaled coordinates.

 

(Caution: this is not a rigorous analysis at all, just a little back-o-the-envelope supposin'.)

 

A little background first. These new maps are available for download from USGS. Go to the USGS Store and click on the "Map Locator and Downloader" link. Then, on the next page, click on the graphic labeled "Map Locater & Downloader Try It Now!" and follow the instructions. You will have to use a recent version of Adobe Reader or Adobe Acrobat, and you will have to download the free GeoPDF Toolbar.

 

Once you do that, you will have a new set of tools when you open up the map PDF.

 

If the USGS has any information about the purported accuracy of the GeoPDF versions of their topo maps, I can't find it, but I did experiment a bit by plugging in the published coordinates of three second order stations. In each case the position as marked by an X by GeoPDF is within the triangle representing the station on the map. The stations I used were —

MILE (HX3035)

MARCY PB AND PP (HV4828)

BURLING PB PP 1930 (HV4835)

 

1393623451_de7d73ebd4_o.gif1393623321_6b27915bc4_o.gif1394517652_fe35e1dbee_o.gif

 

It may well be that this technique could provide more accurate location of scaled marks than using a consumer grade GPS in the field IF (and this is a big if) the mark on the map accurately represents the position of the mark on the ground.

 

Just my two cents here. Further thoughts encouraged.

 

-ArtMan-

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ArtMan:

 

The GeoPDF's, just like DRG's they are made from, are subject to the same National Map Accuracy Standards. In terms of horizontal accuracy, for maps on publication scales of 1:20,000 or smaller, this means that not more than 10 percent of the well-defined points tested can be in error by more than 1/50 inch. For a 1:24,000 scale map this translates to 40 feet. So while the GeoPDF technology allows one to get the coordinates of a tri-station or a BM as its shown shown on a map more accurately than scaling with pencil and ruler, 90 percent of the time the position shown on the map could be off by as much as 40 feet, and 10 percent of the time it could be off by more than 40 feet from where the tri-station or BM is located in the real world.

Edited by tosborn

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Looking at some of the new sheets trying to figure out why my 'tools' quit working I noticed that the 'cooridinate' line has been changed quite a bit. At first I thought that they had just adjusted it, but now I see that instead of just NAD 83 (19xx) it might have NAD 83 (NSRS2007) -- so the possibility of the NSRS letters caused the realignment. The code section below shows the different possibilities now.

 

Also I noticed that we used to have just 'ADJUSTED' or 'SCALED' at the end of these lines. Now there are 2 more 'Hand Held' possibilities. Will be interesting to get some of you more experienced guys to help me figure out the difference.

 

My first question is, are 'scaled' still 'scaled' and HD_Held1 & 2 the equivalent of the old 'adjusted'? or do we now have gradations in between?

 

Here is from around line 240 of the 'Tell Me More' doc for data sheets:

Loading of the National Readjustment data commenced on September 14, 2007.
Before this the format of the position and elevation lines appeared as follows:

AA3495* NAD 83(CORS)-  39 08 02.34046(N)	077 13 15.51884(W)	 ADJUSTED  
AA3495* NAVD 88	 -	   140.76   (meters)	 461.8	(feet)  GPS OBS 

After the readjustment, the position and elevation lines on a datasheet
will appear in a slightly modified format to accomodate the larger datum
tag field (i.e. NSRS2007) as shown in the below examples.
______________________________________________________________
DF9012* NAD 83(NSRS2007)-  42 56 15.39233(N) 071 26 19.03487(W)	ADJUSTED  
AA3495* NAD 83(CORS)	-  39 08 02.34046(N) 077 13 15.51884(W)	ADJUSTED   
RF0849* NAD 83(NSRS2007)-  46 52 08.05186(N) 068 00 53.02328(W)	ADJUSTED
TA0047* NAD 83(1986)	-  48 04 54.20   (N) 090 45 48.42   (W)	HD_HELD1
AC3384* NAD 83(1986)	-  25 57 14.7	(N) 081 43 29.2	(W)	HD_HELD2  
HV0454* NAD 83(1986)	-  38 20 52.	 (N) 076 13 39.	 (W)	SCALED   
DX3756* NAD 83(NSRS2007)-  33 38 08.42412(N) 117 05 10.37961(W)	ADJUSTED 
FQ0856* NAD 83(1986)	-  35 47 36.	 (N) 111 52 56.	 (W)	SCALED	
DB0356* NAVD 88		 -	   -11.886  (meters)  -39.00  (feet)  READJUSTED
DC2131* NAVD 88		 -	  1096.93   (meters) 3598.8   (feet)  N HEIGHT 
AI5086* NAVD 88		 -	   123.68   (meters)  405.8   (feet)  GPS OBS
GP0162* NAVD 88		 -	  1456.97   (meters) 4780.1   (feet)  RESET	  
DE3069* NAVD 88		 -		38.25   (meters)  125.5   (feet)  GPS OBS 
GP0641* NAVD 88		 -	  1831.8	(meters) 6010.	(feet)  GPS OBS  
BW0768* NAVD 88		 -		59.70   (+/-2cm)  195.9   (feet)  VERTCON   
BW2469* NAVD 88		 -	   125.	 (meters)  410.	(feet)  SCALED	 
FG1799* NAVD 88		 -													
TV0377* LOCAL TIDAL	 -		 7.2	(meters)   24.	(feet)  VERT ANG

 

Thanks!

Edited by YeOleImposter

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... Also I noticed that we used to have just 'ADJUSTED' or 'SCALED' at the end of these lines. Now there are 2 more 'Hand Held' possibilities. Will be interesting to get some of you more experienced guys to help me figure out the difference.

 

My first question is, are 'scaled' still 'scaled' and HD_Held1 & 2 the equivalent of the old 'adjusted'? or do we now have gradations in between?

 

Here is from around line 240 of the 'Tell Me More' doc for data sheets:

 [Extraneous material deleted]
TA0047* NAD 83(1986)	-  48 04 54.20   (N) 090 45 48.42   (W)	HD_HELD1
AC3384* NAD 83(1986)	-  25 57 14.7	(N) 081 43 29.2	(W)	HD_HELD2  

Imposter, I am pretty sure that HD_HELD means just that. "Adjusted" is still much more accurate than your consumer grade GPS, and "scaled," meaning interpolated from a topo map, is probably less accurate than your GPS. You'll note that HD_HELD is purportedly accurate to tenths of a second, while scaled marks show round number of seconds albeit with the cautionary note that there could be up to six seconds horizontal error.

 

Putting handheld coordinates into the datasheets is an idea that goes back at least to 2003, even if it has not been widely implemented. See this thread started by DaveD.

 

-ArtMan-

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Putting handheld coordinates into the datasheets is an idea that goes back at least to 2003, even if it has not been widely implemented. See this thread started by DaveD.

 

-ArtMan-

 

Thanks, that was an interesting read. Noticed he was hoping to add coordinate and photo submissions 'in the next couple months' -- that was 4 years ago. Made me think of a new question.... How then are the hand held coordinates submitted? I assumed these were coming from a different source than the NGS recover form since it has no place to submit coordinates (or photos as mentioned in the discussion).

 

YOI

 

UPDATE:

I am guessing the HD_HELD1 & 2 have been in the specifications for quite a while -- they are not new -- just had not paid attention to them before this. Guessing there are only a few sheets out there where these show up?

Edited by YeOleImposter

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YeOleImposter -

 

When a datasheet says, in the horizontal coordinates line, that the coordinates are scaled, it means that someone used a topographic map (or maybe some other kind of map), and then looked around as best they could and put a mark on the map where they figured they had set the mark. (Like here on the south flank of that hill, near where this creek makes this kind of bend, etc.) Then someone uses a ruler (scale) on the topo map to interpolate what the coordinates are. I'm sure you know all this already. The thing is that if someone reports to the NGS the coordinates using a GPS receiver, then it isn't using a scale (ruler), but instead a GPS receiver, so it shouldn't really be called SCALED. So, they picked HD_HELD. There's a recognition that there are 2 levels of handheld GPS receivers; consumer handhelds and professional handhelds, the difference being the number of decimals in the seconds that they can measure. (I think the 2-decimal second units use the ground calibaration station along with the satellites.)

 

Adjustment is a totally different concept. It means that a matrix of information from many survey stations' measured positions in relation to each other are solved with least squares adjustment math so that all the measurments agree with each other as much as mathematically possible. Those that are outliers are adjusted more than those that are not, etc.

 

The reason I say that Adjustment is a totally different concept from scaled or hand held is that adjustment just means that a matrix solution of many measurements was done but it doesn't say anything about the accuracy of those measurements. In fact, someone could use a boy scout compass and some knotted string to measure between a bunch of stations and submit the measurements to an adjustment program and then you'd have adjusted coordinates for each station. (The stations' position adjustments would be large and the whole adjusted net could be significantly off.)

 

In practice of course, the NGS does not bother to adjust a bunch of measurements unless they already meet precision standards of measurement. So, when the datasheet says ADJUSTED, it will mean extremely accurate, not only because of the advantage of matrix solution of measurement data but that very precise measurements were involved.

 

The state of Delaware has a string or two of HD_HELD stations. I made a special color coding for them in ngsread when I first wrote it.

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UPDATE:

I am guessing the HD_HELD1 & 2 have been in the specifications for quite a while -- they are not new -- just had not paid attention to them before this. Guessing there are only a few sheets out there where these show up?

I think that's the case - as when I first even thought about making my program, about a year ago, I looked at that 'Tell me More' link, and I remember seeing those there then. I've never seen one IN a datasheet, tho. :P

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HD_HELD is pretty uncommon. I just searched through the three largest county archives in the Washington, DC, area (Prince Georges and Montgomery in Maryland and Fairfax in Virginia), covering a total of almost 17 megabytes of data in the .DAT files, and got a grand total of three stations with HD_HELD coordinates. (Many more, of course, may have included consumer-grade GPS coordinates in the text of recovery reports.)

 

-ArtMan-

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fyi

 

There are various Horizontal Control sources, as specified below:

		ADJUSTED = Least squares adjustment.
				   (Rounded to 5 decimal places.)

		HD_HELD1 = Differentially corrected hand held GPS observations.
				   (Rounded to 2 decimal places.)

		HD_HELD2 = Autonomous hand held GPS observations.
				   (Rounded to 1 decimal places.)

		SCALED   = Scaled from a topographic map.
				   (Rounded to 0 decimal places.)

 

Here is a LINK to what various things on ds mean

Edited by Z15

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When a datasheet says, in the horizontal coordinates line, that the coordinates are scaled, it means that someone used a topographic map (or maybe some other kind of map), and then looked around as best they could and put a mark on the map where they figured they had set the mark. (Like here on the south flank of that hill, near where this creek makes this kind of bend, etc.) Then someone uses a ruler (scale) on the topo map to interpolate what the coordinates are. I'm sure you know all this already. The thing is that if someone reports to the NGS the coordinates using a GPS receiver, then it isn't using a scale (ruler), but instead a GPS receiver, so it shouldn't really be called SCALED. So, they picked HD_HELD. There's a recognition that there are 2 levels of handheld GPS receivers; consumer handhelds and professional handhelds, the difference being the number of decimals in the seconds that they can measure. (I think the 2-decimal second units use the ground calibaration station along with the satellites.)

 

My experience might be limited, but I'd go by those little Xs on the topo maps over scaled coordinates, in many cases. I think they drew the X on the map properly, but something got lost in transcription.

The accuracy of Hand Held consumer grade GPS units might not be reliable (so I can see why NGS might have problems with them.) But, in many or most cases, for scaled coordinates, I'll take a semi-decent GPS reading over the scaled coordinates. Not counting the typo errors, 300 feet off is not unusual (scale of error), but I've run into a fair number that were much further off than that.

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My experience might be limited, but I'd go by those little Xs on the topo maps over scaled coordinates, in many cases. I think they drew the X on the map properly, but something got lost in transcription.

The accuracy of Hand Held consumer grade GPS units might not be reliable (so I can see why NGS might have problems with them.) But, in many or most cases, for scaled coordinates, I'll take a semi-decent GPS reading over the scaled coordinates. Not counting the typo errors, 300 feet off is not unusual (scale of error), but I've run into a fair number that were much further off than that.

 

I don't think anyone would disagree with you. Before going out to hunt any scaled mark I will look to see if it shows up on the USGS topo map. I usually use ACME Mapper because the crosshair allows me to center it on the benchmark X and then I can copy the lat/lon and paste it into the corrected coordinates for GSAK.

 

-YOI-

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NGS is working on an update to the on-line recovery program that will allow all the bench mark hunters to provide hand-held GPS values (HD_HELD1 or HD_HELPD2) to update the scaled values in the NGS database. This was supposed to be completed some time ago, but the requirements for programming support for the national readjustment put this task on the back burner. The update to the utility will also allow you to add digital images as well. I am hopeful that will be addressed during the coming fiscal year.

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NGS is working on an update to the on-line recovery program that will allow all the bench mark hunters to provide hand-held GPS values (HD_HELD1 or HD_HELPD2) to update the scaled values in the NGS database. This was supposed to be completed some time ago, but the requirements for programming support for the national readjustment put this task on the back burner. The update to the utility will also allow you to add digital images as well. I am hopeful that will be addressed during the coming fiscal year.

Maybe someone else has another take on it, but.. I don't understand the usefulness of the digital pictures on a datasheet. Aside from that, how will they be provided? I don't see actual surveyors looking at a datasheet and wanting to see the picture of the mark. :anitongue:

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Maybe someone else has another take on it, but.. I don't understand the usefulness of the digital pictures on a datasheet. Aside from that, how will they be provided? I don't see actual surveyors looking at a datasheet and wanting to see the picture of the mark. :anitongue:
Right now, the few pictures available are linked to datasheets but the images don't actually appear on the datasheet itself. That's manifestly inconvenient. One possibly solution might be to have the current text+link system, but add a button to create (on the fly) an integrated datasheet with pictures. It could then be printed out and taken into the field.

 

I am not a surveyor (IANAS), but it seems to me, with all respect to foxtrot-xray, that if I were a professional to who time is money and I was sitting in my office thinking through a project, it would be extremely helpful to have pictures to help visualize the situation, and similarly in the field those pictures might help a crew orient themselves and may shave some time off the actual finding of a hard-to-find (or badly described) mark.

 

My two cents only.

 

-ArtMan-

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Different people take different pictures, but the kind of picture that is of the most importance here is the 'distant' picture, or what the NGS calls the horizontal view. This is the type of picture, taken several feet away from the mark, that clearly shows where the mark's position is in relation to its surroundings. This one type of picture is the most important in getting across information to surveyors about how to find the mark. The closeup picture is not important for finding the mark - it only serves to show that the correct mark was found and something about its condition.

 

The type of picture that is of zero importance is the one taken "from the mark" with the mark not in view. One not much less useless is the type of picture that supposedly shows where the mark is in its surroundings, but there's no way to spot the mark in the picture and there's no arrow or object to indicate where it is in the picture. I have run across several of these when looking for good pictures for the photo 'contest' but, try as I might, with a magnifying glass or whatever, I could not find the mark in the picture.

 

The NGS requrements for digital pictures of survey marks is here. Take note, however, that these requirements are for surveyors or surveying firms submitting marks for inclusion in the NGS database (bluebooking), and not for people submitting mark recovery photos (I think there are no such requirements spelled out yet). One thing I don't like about these requriements is the use of paper labels for the marks. I prefer to use a photo editor to put in an arrow and label. :anitongue:

 

A year or two ago, I chanced to see the future NGS mark recovery form that had places to enter handheld lat-lon data and photo submissions. This is to answer the wondering about whether they have done such a form - they did already and it looks good. (In case someone intends to ask, I found it with a search engine; it was on some non-NGS website that had the link to it on the NGS website. I wrote Deb and she said that it was an oversight that it was on a part of the web the public could see. <_< It was later removed, I noticed, and I never saved it.) So as DaveD indicates, the form is not the problem; the programming to use the form is more the issue of when the form can be used.

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The closeup picture is not important for finding the mark - it only serves to show that the correct mark was found and something about its condition.

 

I have found a few marks which were 50-year-old crosscuts in concrete steps, etc. They are barely evident, and you wouldn't know they were there unless you looked closely for them. I marked out a few with keel (lumber crayon) and photographed them close-up. They would come in handy for somebody looking for them under less-than-ideal conditions.

The type of picture that is of zero importance is the one taken "from the mark" with the mark not in view. One not much less useless is the type of picture that supposedly shows where the mark is in its surroundings, but there's no way to spot the mark in the picture and there's no arrow or object to indicate where it is in the picture. I have run across several of these when looking for good pictures for the photo 'contest' but, try as I might, with a magnifying glass or whatever, I could not find the mark in the picture.

I keep a 4-foot sight rod in the car and jam it into the ground behind the marker when taking a surroundings photo where it is not visible.

The NGS requrements for digital pictures of survey marks is here. Take note, however, that these requirements are for surveyors or surveying firms submitting marks for inclusion in the NGS database (bluebooking), and not for people submitting mark recovery photos (I think there are no such requirements spelled out yet). One thing I don't like about these requriements is the use of paper labels for the marks. I prefer to use a photo editor to put in an arrow and label. ;)

I wrote to Deb Brown back in January about submitting photos. My company had been photographing several markers in connection with some of our projects and I figured they could become useful for others. She replied that the standard for submitting recovery of existing monuments was less restrictive. reduce them to no more than around 500 kb (resizing to around 1000x800 will make them less than 300 kb). Edit the picture to include a note to its name, PID, view (1 is closeup, 2 is eye-level, 3N would be marker and surroundings looking north). Paper labels beside the marker are not required, although I was using them on some of my earlier photos. They are to be submitted by mail on a CD to NGS.

 

I submitted a set of 40 back around March or April. It included structures (even though they probably wouldn't want to be bothered with them, but I had photographed them anyway), and marks (disks, structures) lost, not found or destroyed to document their destruction. I submitted another set of maybe 80 markers and structures in June. So far I haven't seen any of them referenced in the datasheets and I am starting to wonder if I should even bother. I have at least another hundred monuments already photographed (someday I get around to posting them).

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The logic in the NGS requirement for a sign in the photographs (#2 and #3) is to help ensure that photos are not mistakenly switched in the office. I have found cases where this happened. The sign does not have to be paper, it can be a white board and reused. The purpose for photo #1 is to be able to read the stamping on the mark. Photo #2 is to show the area immediately surrounding the mark - is there an erosion problem or some other issue with the security and/or permanence of the mark. Photo #3 was designed to show the surroundings, including the nearest satellite obstruction, and also help in recovering the mark. Ideally, photo #3 includes a tripod over the mark so the mark location can be easily seen.

 

Regarding the new data sheet format, NGS will shortly be issuing additional clarification.

GEL

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NGS Surveyor -

 

For recovery report purposes, and in the interest of getting more recovery pictures submitted, I believe that an allowance for photo-editing annotations more or less like those in these two photos would be a good solution to a tradeoff situation. I see your point about possible office mixups, but if hunters of PIDs are going to be required to make and bring physical signs, I think it might significantly reduce the number of pictures submitted.

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In my opinion if you start making too many requirements for volunteers they tend to do less.

 

It is the main reason for volunteering there are no "Restrictions",or very few.

 

I tend to do some on the fly,if I spot a witness post states away I may not have a truck full of all the required goodies.

 

I may not even have a data sheet to refer to for reference objects.

 

But I do try to get most of the things nearby to use for reference.

 

Just my 0.02

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A couple of quick comments...

 

When some friends and I were in Yosemite recently, it took exactly two benchmarks for my friends to switch from using the NGS scaled coordinates to my map-derived coordinates, because I was the one who kept walking right up to the marks. :o I use MacGPS Pro with digital raster graphic (DRG) 7.5' quads downloaded from the California Spatial Information library.

 

I include coordinates in my recovery reports when the scaled coordinates on the datasheet are off by more than 200-300 ft. (The worst case I've found so far was 1/4 of a mile.) I just put them in the additional comments box, using the same format as the other coordinates on the datasheet, prefaced by "Handheld GPS coordinates." It'll be nice if sometime there's a specific field for handheld entries.

 

Patty

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Granted, this group gets some really great photographs of benchmarks, and it would be cool to show off our picture-taking skills to users of the NGS database.

 

But let's face the fact that taking photos is the most tedious part of benchmark recovery, even without the special requirements of NGS. On one expedition, my camera failed around mid-afternoon. I continued making recoveries without taking pictures. (The spare camera uses 35mm film, and there was nothing special about the remaining marks that justified the expense of film processing.) I was amazed how much faster things went in the field, and how easy it was to upload my recovery notes to GEOCACHING.COM!

 

Except for really long hikes to a benchmark, I leave the camera in the vehicle until the mark has been found and the references have been checked. (This keeps it from getting banged up while digging, and while using the metal detector, etc.)

 

Generally speaking, I'll take pictures if:

 

*it isn't raining; and

*it isn't too far back to the car; and/or

*it looks like I can get a shot which qualifies for the benchmark photo contest. :o

 

Upon returning home, there's the uploading from the camera, followed by resizing and adding labels and/or arrows. Next comes the entry phase. Even small files take time up upload to GEOCACHING.COM, and one must use care to get the correct photos for each entry.

 

For me, it is a relief not to deal with photos for NGS recoveries. I simply cut and paste from the notes typed up in advance. About two years ago, I sent in photos for a couple of benchmarks. These were situations where a picture truly was "worth a thousand words". However, it proved to be very labor-intensive and I quickly abandoned the practice. In the field, carrying markers and white board for signs was cumbersome and time-consuming. (I'd much rather add labels using my computer.)

 

It is a different story for mark-setting organizations like GEOMET. Taking digital photos is a minor part of the process. And the monumenting party is being paid for what it does.

 

For hobby recoveries, I think we're doing a great job for NGS without the pictures. And if someone is really curious what the scene looks like at a particular benchmark, refer them to this site. :D

 

-Paul-

 

P.S. Like Patty, I include my GPS reading (usually averaged for three to five minutes) on marks with SCALED coordinates. I preface them with the phrase HH2 GPS COORDINATES......

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