Need sanity check from actual pilots (state plane)

[DroneNerd702]

If you fly real planes, perhaps you can help me do a sanity check.
I'm using this tool for my county in conjunction with the county assessor's info to determine property boundaries.
GISMO

Pick any point of interest and use the drawing tool to place pins on the top left, top right, bottom left and bottom right of a boundary. Get the State Plane value for one of the points then, use this tool to convert to Lat / Long.
State Plane Coordinate System

Now, input the lat / long value into Google maps. Does GM bring you to that location?

It's not working for me and I'm wondering if the clark.nv app is inaccurate. Because, one sanity check I did was start at the opposite. I got a lat / long value from Google maps, used earthpoint to convert the value to State Plane coordinates, and clicked it's button to fly me there with Google earth and it put me in the general area. Not in the middle of the North Pacific ocean.

Anyway, I must be doing something wrong starting at the clark.nv site. Hoping someone with piloting, surveying, mapping experience can help me figure it out. It's not like I'm dumb with maps. I can use maps and have many years land nav'ing with US Army grid maps. So, I don't know what's happening here. Thanks in advance for shedding some light.

 

[Eric Sheehan]

The longitude value(s) should be negative, if you are placing coordinate values in the US. If you post the numbers you are using, in state plane I can take a look. Google may not provide that as it is implied. Need to know state plane zone and datum from county source.

If you plot the longitude in positive, most softwares will put you that distance east of prime meridian.

 

[DroneNerd702]

The longitude value(s) should be negative, if you are placing coordinate values in the US. If you post the numbers you are using, in state plane I can take a look. Google may not provide that as it is implied. Need to know state plane zone and datum from county source.

If you plot the longitude in positive, most softwares will put you that distance east of prime meridian.

I can't seem to find zone information for the location I want through the clark county web site link. But, I noticed too that I wasn't inputting the values in as negative numbers. Here's an example of the State Plane numbers I obtained and used as a practice exercise. My lat/lon values are most probably imprecise but not the State Planes which I got directly from the mouse pointer position on the web site which updates in real time when you move the mouse to a new location. Trying to obtain data for plotting a test mission in Tower but, need to get past the hump so I can get the precise GPS coordinates for cross-referencing against a waypoint in Tower. Not sure if I'm even going about this the right way.

Pins top right to bottom right
State Plane x: 721844 y: 26756946 (intersection at green dotted line)
Degrees Lat Long 71.3824527°, -135.0376378°

State Plane x: 721897 y: 26755610 (intersection at green dotted line)
Degrees Lat Long 71.3789911°, -135.0341351°

State Plane x: 721937 y: 26754631 (near first set of trails)
Degrees Lat Long 71.3764553°, -135.0315597°

State Plane x: 721951 y: 29754288 (intersection at dark blue line)
Degrees Lat Long 78.9929474°, -146.9310681°

State Plane x: 721971 y: 26753182
Degrees Lat Long 71.3726836°, -135.0279559°

 

[Eric Sheehan]

I'll load these up tomorrow morning

 

[DroneNerd702]

I'll load these up tomorrow morning

Thanks man. Will be interesting to see what your results are and hopefully, help me discover what I did wrong.

 

[Eric Sheehan]

Plotting those state plane, you are in a canyon south of hwy 159, west of red rock country club? I'll send you a map and converted lat-long in a bit. The numbers I got were different. You may have x-y reversed when convert to lat-long. Latitude is y coordinate.

 

[Eric Sheehan]

x_coord y_cord lat long

721844 26756946 36.151781 -115.36086

721897 26755610 36.148111 -115.360691

721937 26754631 36.145421 -115.360563

721951 26754288 36.144479 -115.360519

721971 26753182 36.141440 -115.360459

 

[DroneNerd702]

Plotting those state plane, you are in a canyon south of hwy 159, west of red rock country club? I'll send you a map and converted lat-long in a bit. The numbers I got were different. You may have x-y reversed when convert to lat-long. Latitude is y coordinate.

That's weird because I got the

Plotting those state plane, you are in a canyon south of hwy 159, west of red rock country club? I'll send you a map and converted lat-long in a bit. The numbers I got were different. You may have x-y reversed when convert to lat-long. Latitude is y coordinate.

Reversed x y SP? That's weird. How I did it was zoom into a point with my mouse and got the values from the little box on the left.

 

[DroneNerd702]

x_coord y_cord lat long

721844 26756946 36.151781 -115.36086

721897 26755610 36.148111 -115.360691

721937 26754631 36.145421 -115.360563

721951 26754288 36.144479 -115.360519

721971 26753182 36.141440 -115.360459

Did you use the same link for the conversion or did you use a different site and methodology?

 

[Eric Sheehan]

I typed in the x-y, plotted to map in state plane, verified location, then converted to Lat Long. The lat-long values you have are way too high for that area. I used a GIS software to plot the points and convert to Lat-Long, using datum of WGS84. If you type the decimal degrees numbers I listed, in Google or other, you should be able to verify and create waypoints in Tower.
From there I think you can set the Solo to "Loiter" at those waypoints, but do not know if the time frame is indefinite. I'll upload the map I created of your points to my account and send to you. The fourth state plane y coordinate had a typo, I assume, I changed the second digit from a nine to a six.

 

[Eric Sheehan]

By reversed x-y I mean you could have supplied the x coordinate as the latitude, and the y coordinate as the longitude when you converted the points.

 

[DroneNerd702]

I typed in the x-y, plotted to map in state plane, verified location, then converted to Lat Long. The lat-long values you have are way too high for that area. I used a GIS software to plot the points and convert to Lat-Long, using datum of WGS84. If you type the decimal degrees numbers I listed, in Google or other, you should be able to verify and create waypoints in Tower.
From there I think you can set the Solo to "Loiter" at those waypoints, but do not know if the time frame is indefinite. I'll upload the map I created of your points to my account and send to you. The fourth state plane y coordinate had a typo, I assume, I changed the second digit from a nine to a six.

Thanks. Much appreciated. I'll pick four of them to use as a small test once the weather is good.

 

[DroneNerd702]

By reversed x-y I mean you could have supplied the x coordinate as the latitude, and the y coordinate as the longitude when you converted the points.

I just discovered in Gismo that I can also specify decimal degrees, get that value, as well as the state plane values. Strange.

 

[Eric Sheehan]

Ok, good to go then?

 

[DroneNerd702]

Ok, good to go then?

Heck-if-I-know. I haven't sanity checked / cross verified the decimal degrees yet. For all I know, those values in Google maps will put me somewhere in the Red sea. Lol. I'll get around to it later this afternoon.

 

[DroneNerd702]

Eric, I just checked. The decimal degrees that Gismo provides is accurate and Google maps takes me to the same spot.