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13

Landsat is available back to the 80s, it may overlap the dates of your project, excepting of course the 1950s. edcsns17.cr.usgs.gov/NewEarthExplorer/ will let you easily browse the archive, once you apply for a username. With that in mind you could potentially get a series of three satellite scenes, two of which tie in with the aerial imagery. For ...


9

I had the pleasure of working with the foremost surveyor in my community on a few occasions. He is actually "the surveyor" that businesses & government bring in to fix/correct inaccurate surveys. In my case, I am not versed in surveying techniques, but I do have the basics pretty well figured out. I have been out capturing x,y,z data for the ...


8

I'm not a surveyor, so take this with a grain of salt. If your students are still being trained to use equipment that requires line-of-site, then my own property points out an interesting challenge. Except for a couple of cases, no two consecutive corners of the property are visible from one another. Thus, to locate them, you need to use auxiliary points ...


7

The budget solution is to calculate relative positions from a corner stake. You will need a compass, a clinometer, a tape measure, a notebook, and an assistant. Starting at the known location, take readings for azimuth, inclination, and distance from the base point to your point of interest. If the point of interest is distant or around obstacles, you can ...


7

You need to know the coordinates of at least one point in lat/lon degrees. If you don't have any surveying points, you might take coordinates from a GPS unit if the point is visible. Using QGIS, you could create the other points of the polygon with the Azimuth and Distance Plugin. Take care to convert the degree-minute bearings into decimal degrees. With ...


6

GRASS GIS can do the same job: http://grass.osgeo.org 3D tutorial volume calculation: r.volume nviz visualization tool:


6

Seems like the picking key points portion of generating a TIN could suit your purposes. Here's a nice discussion on TINs, with three algorithms for picking key points. Survey of Polygonal Surface Simplification Algorithms would also be a good place to start.


6

The answer is quite simple: "Spot heights – shown as a number beside a dot – appear at strategic points, including along roads where they level out at the top or foot of a hill. These can be a useful guide where there aren't many contour height numbers."


5

Hiring a surveyor a Mapperz suggests is probably the most sensible thing to do if you're committed to putting a lot of money into landscaping. That said, see if there is LIDAR data available for your area. Some U.S. states provide it at an accuracy of ~18cm for free. It might be sufficient for your planning needs.


5

Grid convergence is the angle between true north and the grid north. It varies from point to point except in cylindrical projections, for which all meridians are parallel. For conic projections the meridians all radiate from a central point (off the map to the north in the Northern hemisphere), making it clear the convergence changes as you move in an ...


4

Honestly, you sound like just the kind of person Esri developed parcel fabrics for. I would recommend watching (or at least skimming) this hour-long webinar to see just what you can (and can't) do with parcel fabrics.


4

your question is not clear but anyway let me try if it is useful to you. 1). Differentiate various types of north---- True north .... i.e Meridian Line(azimuth) (meridian of the place where you are) Grid north .... i.e Horizontal and vertical lines making grid (each vertical line pointing towards the grid north of that line) Magnetic north ... i don't ...


4

I recommend mapping the XY coordinates using QGIS. This will create a Point shapefile. There are many posts about how to do this. Next, if don't have the landgrid shapefile containing Township/Range/Section data, it should be easy to find on the Internet, search for "State Name" GIS data. Finally, Intersect the two shapefiles using QGIS. Each Point should ...


4

According to Map Check in Copan User Manual, each call is of the form to-point bearing distance <blank> <blank> <blank> as you (sort of) say. However, the first "call" must have (only) the initial start point (and optional label): from-point <blank> <blank> trav-label <blank> <blank> In other words, a traverse ...


3

Parcel Fabrics add a lot of overhead to manage. I would say it is worth it IF: 1) you need to manage the legal descriptions of the properties 2) you need the accuracy to be survey grade (which it appears you don't) 3) you need to manage parcel changes over time (subdivisions, boundary line adjustments, etc.) From a county government perspective, it is ...


3

It's possible to do this kind of work using close-range photogrammetry, which basically involves taking a lot of pictures and then working with them on a computer. Unfortunately, good software for this costs US$1k-$3k, and it takes some practice to use it well and to take the right pictures. It's a lot of fun, though.


3

DIY Survey on the cheap is going to be either inaccurate (cheap equipment) or costly. Ideal renting a viva gs09 rtk would be your best bet http://www.surveyequipment.com/gps-survey-equipment/viva-gs09-rtk (Requiring only the GS09 SmartAntenna and CS09 Controller) Then you need the software to create your DTM. The really dirty way is create a grid in your ...


3

This sounds like it might be more of a landscape architecture problem than a surveying problem. Google Sketchup allows you to enter relative coordinates. There's a Pro and a free version. Use that in conjunction with a Laser distance tool.


3

Setting up anchored poles at the corner rebars could help with either getting a straight line across, or with optical triangulation once you have a line of sight. The accuracy will depend highly on your optical equipment in the latter case. I guess you could rent a theodolite (or a professional land surveyor) for the task if that is in budget.


3

Welcome Lucy -- your question is a little bit unusual for this site, which mainly caters to people who use geographic information systems professionally or in research. I found it surprisingly hard to google up a site that has a concise history and comparison of navigation tools over time. However, I think the Smithsonian Museum's Time and Navigation site ...


3

Legal plans (plats) and legal descriptions are not in any projection (grid) system; they are on a local, ground-based plane. Hence the need for grid-to-ground and ground-to-grid conversions. As a minimum, there are usually scaling and rotation issues to deal with. So, it is quite possible that neither GIS nor legal description are wrong. Once we get more ...


3

In QGIS you can use the Interpolation plugin (I think it is installed by default, if not it is a standard plugin installed through Plugin Manager) found in Raster -> Interpolation. With that plugin you can take your vector layer of points and turn them into either a TIN or a surface model. You can either pull the elevation from a field in an attribute ...


3

Disclaimer: Any method you use to do this, especially with a consumer GPS unit, is going to be an approximation at best. If you truly want to know where the boundaries are, you will need to locate property pins/corners which might require a metal detector. Your best, safest option is to hire a professional land surveyor. No, those are not lat/longs in the ...


3

Form (whole circle) bearing, zenith angle and horizontal distance to X, Y, Z X = X0 + h_distance * sin(deg / 360 * pi()) Y = Y0 + h_distance * cos(deg / 360 * pi()) Z = Z0 + h_distance / tan(zenith / 360 * pi()) X0, Y0, Z0 are the coordinates of the station deg / 360 * pi() changes angle from deg to radians Horizontal distance from slope distance and ...


3

DISCLAIMER: Please see important caveats at end of message. SHORT ANSWER: The average absolute latitude of land on Earth is 33.2924 degrees, or about 3764 km from the equator. Longer Answer The plot above shows the kilometers of land intersected by line of latitude sampled every 1.8' (6000 samples total). Some notes: The large bump on the left ...


2

It almost seems as if there was some additional information I am not getting in the "raw" files such as breaklines From the snippet you show, no you don't have any breaklines. With the data you have, I would be doing the exact same process that you are. AutoCAD will not yield better results if using the same data. Any chance you could show 2 ...


2

ArcGIS Survey Analyst extension supports .gsi import Survey Analyst imports and exports measurements and other field data from Total Positioning System (TPS) equipment using the following survey data converter formats: ASCII converter, Geodimeter converter, GSI converter, SDR converter, TDS coordinate converter, and TDS raw converter. The data import ...


2

There are some extensions of the douglas-peucker filtering algorithm to 3D surfaces. See for example this paper.


2

AutoCAD Civil 3d is the software that I use for cut and fill jobs. Once you create a surface as a triangulated irregular network (TIN) that represents the existing ground, and another one that represents your desired surface, it will tell you how much dirt you need to move. It is available as a free trial from AutoDesk. I believe that the only ...


2

You could have a look at the techniques used for orienteering mapping.



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