Planning to take a gazilion topo shots, and would like to bring them into Google Earth Pro. There seem to be a vast number of ways to do this. I'm not interested (at the moment), in true, precise localization. I have a single point whose Lat and Long I've assumed. All the other point coordinates could be/would be referenced to that one point.
My first thought was Carlson X-port, but I think my version of SurvCE (2.5) is too old to qualify for a license. Any ideas on the most straightforward way to do this?
> My first thought was Carlson X-port, but I think my version of SurvCE (2.5) is too old to qualify for a license. Any ideas on the most straightforward way to do this?
"Straightforward" is a relative thing. Based on what I've read -- with some reading between the lines -- here's one approach:
1. Convert your single lat/long position to a plane coordinate. SPC, UTM, whatever suits you.
2. Translate your surveyed points onto the known coordinate. You can use whatever COGO application you have available to do this.
3. Decide upon a basis of bearings that's somewhere close to reality. I infer that you only have a single known position, and if that's the case you'll have to rely on a record bearing, compass bearing or by-guess-and-by-golly bearing to orient the rest of your points.
4. Rotate your surveyed points around your known point using your chosen bearing basis using your COGO application.
5. Export your coordinate points to a standard ASCII format (typically some flavor of CSV).
6. Use CORPSCON to convert your coordinate file to a lat/long ASCII file. You'll have to pay attention to the file formats to get this to work correctly, but once you set it up it's easy.
7. Use GPSBabel to convert your lat/long file to KML.
8. Open the KML in Google Earth.
Thanks for this thoughtful reply. There's a whole lot to think about there. I had it in the back of my brain that this endeavor would be a good way to "dip my toes" into the whole "Grid to ground" thing, in spite of the fact that for this topo project I don't need the accuracy, but I'm feeling the rip tide sucking me in already.
But I'll fill in one blank on this one for now:
> 3. Decide upon a basis of bearings that's somewhere close to reality. I infer that you only have a single known position, and if that's the case you'll have to rely on a record bearing, compass bearing or by-guess-and-by-golly bearing to orient the rest of your points.
Not going to rely on "by-guess-and-by-golly bearings".
I've got one "record bearing" from a survey of an adjacent property, sharing the single point, done last year completely with GPS.
Not wanting to rely on that alone, I've done two Polaris observations from the single point. But I'm not confident of the results to less than 20" as I recall, so I'm planning a bunch more, both at that spot, and then, as I traverse about, taking additional Polaris observations from any location that has visibility of the star, and then adding them to the LSA pot (don't know yet how to weight them, but that's another thread).
I have more questions about your proposed process, but there's a lot there to digest.
Thanks for the input.
Download Carlson X-Port and apply your licensing key, you may get what you need.
😉
Tried that. Says "not valid". I'll call them on Monday and see what's up.
RW5 is a raw data collection format. You need to reduce that to cartisian coordinates. Then convert to geographic coordinates.
There are many CSV to kml converters, search google.
You mentioned you have one point close to known datum. You will also need a basis of bearing, which requires two points. Are you performing a sunshot?
> RW5 is a raw data collection format. You need to reduce that to cartisian coordinates. Then convert to geographic coordinates.
>
> There are many CSV to kml converters, search google.
>
> You mentioned you have one point close to known datum. You will also need a basis of bearing, which requires two points. Are you performing a sunshot?
Understood. I'm going to use Polaris. I think I have the gist of what you and Jim Frame are suggesting, but what "north" does Google Earth use?
Google Earth uses Geographic Coordinates = Latitude and Longitude = Geodetic North
With a Polaris observation you will be determining Astronomic North, which is different from Geodetic North by the LaPlace correction.
The LaPlace correction is very small, in the order of 7 arc seconds around here.
Setting Bearing From A Single Point
Use your photo and two very distinguishable points to establish a photo bearing.
Common points I have used often are the center ends of parking lot stripes, inside corners of curbs, asphalt to concrete transition points; points I know I can easily distinguish in the field. It is better to have 3 or 4 such points to verify that your selection set is good.
I am setting up 2 jobs right now to hopefully bang out next week, i.e. when the snow is finally gone. One has established bearing from distant points, exactly where, I don't care, on the centerline stripes.
Understanding how big a photo pixel is, +/- 0.5' (feet) is a precise result
Paul in PA
Install the latest version of the SurvCE emulator on your PC, then open the RW5 file and export KML directly.
m
> Install the latest version of the SurvCE emulator on your PC, then open the RW5 file and export KML directly.
>
> m
This may actually work, although There are two options for "position source". Geodetic (Lat/Lon/Hgt), and "Export Grid (XYZ)". I'm not sure I've ever gotten a "real" geodetic azimuth into a data file yet on the DC. But I think if I orient two points (say my BS to my POB), relative to geodetic north, then let COGO come up with the XYZ coordinates for all the points, that might work.
In SurvCE, Under "Equip", "Localization", "Points", it looks like I can orient all the rest by simply picking two points whose coordinates have been calculated. I've never looked at that screen before this though, so I guess it's time to read the manual.:-/
> Install the latest version of the SurvCE emulator on your PC, then open the RW5 file and export KML directly.
Where can the emulator be found? I have an older version of it installed on my system, but it doesn't have KML support. I looked on the Carlson website and couldn't find any version available for download.
> > Install the latest version of the SurvCE emulator on your PC, then open the RW5 file and export KML directly.
>
> Where can the emulator be found? I have an older version of it installed on my system, but it doesn't have KML support. I looked on the Carlson website and couldn't find any version available for download.
It's called SurvPC. 4.03 I think. You can run it without a survCE license in demo mode limited to 15 points, but the export option seems to be there.
Try this
http://ashgps.com/mirror/Carlson/SurvCE/4.02_31Oct2014/SurvCEDemo.exe
If your raw file is gun based you can resection in the emulator.
M
If your data consists primarily of GPS measurements, check out the Carlson EMEA RW5 Report Generator ( http://www.carlsonemea.com/cwa/report/index.php?lang=ENG ) developed by one of my previous European-based colleagues.
My TDS data collector stores Lat/Long directly into the RW5 files when I'm doing a GPS survey, and can also export points as Lat/Long.