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left click on GCPs not dropping a marker

Using Chrome; tried to use GCPs for the first time, following the tutorial. When I left click on the location, no blue marker appears as in the video. No marker appears on the map to the right either. Suggestions?

Luis Martinez

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Dropping the marker to designate a GCP is done with a right click, not a left click.

Elizabeth
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the right click works on the left side, but places the marker way off, have to swag it in to the GCP by multiple right clicks. Nothing works on the map, left or rightclick.

Luis Martinez 0 votes
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It assumes a screen of a certain size. The marker being off usually happens on smaller laptop screens. We are likely going to be getting rid of those workflows because they are using a lot of problematic controls.

Tudor 0 votes
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As Tudor said, the GCP system does work but it is a bit temperamental. Please try it on a larger screen to make sure that all the popup windows fit and follow the instructions in the guide.

Elizabeth 0 votes
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these are the steps I followed

For each pre-selected object:

  • Click "Add New GCP".
  • Click Choose File and select one of the images in which the object the measurement is present.
  • Zoom in and right click on the object in the image where the measurement was taken. A marker will be drawn on the basemap as a visual check.
  • Enter the Latitude, Longitude and Elevation values for the location designated in the image.
  • If everything looks good, click "Save".
  • Click "Add New GCP" again to create the other GCP to be used in the anchor point.
  • The Latitude, Longitude and Elevation numbers that were defined on the previous GCP are automatically populated.
  • Click Choose File and select another image (not the same as before) in which the object is present.
  • Press the orange "Reuse this location" button to use the EXACT location again.
  • Zoom in and right click on that same object in the image. Again, make sure to select the exact area of the object that was selected before.
  • If everything looks good, click "Save".
  • The table should be shaded green to show that these points represent on of the 3 required anchor points.
  • Repeat this process for at least two more anchor points.

I have 3 points on the table. Am trying to follow the video tutorial but either click, left or right, does not drop any markers on the map?

Luis Martinez 0 votes
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You need to have 6 points in the table. 3 different ones and then 3 that have use the "Reuse this location" button to make the Anchor Point pair. Then you have to do one extra.

The table should look like this:

Each of the matched colors represents an Anchor Point.

 

Elizabeth 0 votes
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ok, when I select a second GCP the SAVE button remains greyed out. Sorry I am not getting this.

Luis Martinez 0 votes
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So clicking on the map on the right side is no longer valid? per the video?

It would be helpful to get one complete set of instructions, beginning to end, skipping no step and not assuming the user has done this before. Thank you.

Luis Martinez 0 votes
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I tried but I keep getting green shade on all my points.

Luis Martinez 0 votes
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You don't use the "Reuse this location" button for all of the points. This is what is making all the lines green. You only use that button for saying "make this point the same" so the GPS coordinates will be exactly equal. It should be used as for the second image for each pair.

Two GCPs makes an Anchor Point. The first one is selected from the image and on the map. The second one is created by using the "Reuse this location" button on the right and choosing the same part of the same object in a different image on the left.

Elizabeth 0 votes
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if I don't click on "Reuse this location" the SAVE button remains greyed out...

Luis Martinez 0 votes
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It is greyed out until you make a point on the right and on the left. If you don't "Reuse this location" you need to give it one.

Elizabeth 0 votes
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"It is greyed out until you make a point on the right and on the left.

RIGHT means the map? That's how I began my question, Ryan. Nothing works on the map, left or right click.

Luis Martinez 0 votes
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If right clicking on the map doesn't drop a marker at all there could be a javascript error or something. Are the coordinates at the bottom updating? We have tested this on Windows and Mac with Chrome, Firefox, and Safari (Mac only) and it seems to be working fine.

Elizabeth 0 votes
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Ah, that could be the problem. I see no coordinates, using Chrome.

I will try updating Java.

Luis Martinez 0 votes
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Java is not involved so don't worry about that.

In Chrome, go to the View Menu -> Developer -> Javascript Console.

Let us know if there is any red text in there that denotes an error.

Elizabeth 0 votes
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Ryan, tried Chrome, Mozilla and a different computer, no luck.

Luis Martinez 0 votes
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That is a bit of a different topic, but in general, consumer level GPS is only good to within a few meters (5-10). A lot of companies will tell you they are better than that, but aren't telling the whole truth. Yes, you can have a bunch of relative measurements maintain a shape, but if you turn it on and off and on and off again you will likely get three different numbers from single samples.

When you look at how much money DJI likely spent on the GPS receiver and antenna portion of the flight control system, it is probably less than $100 of your cost. Don't expect even OK GPS precision out of anything that costs less than $25k for still measurements and $100k for moving ones...

That being said, DJI does a pretty good job for the cost.

Even Google doesn't stand by it's numbers. Read more here:

http://support.dronesmadeeasy.com/hc/en-us/community/posts/204562556-Google-Earth-Vertical-and-Horizontal-Accuracies

 

Elizabeth 0 votes
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Understood. Thanks. Let me know if you think of anything else that could be stopping my computer from dropping markers in the map side.

Luis Martinez 0 votes
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Are you sure you were on the basemap georeferencing workflow? If you were on the Manual GCP workflow you would not be able to right click on the map to define the point. For the manual GCP workflow you are supposed to type the values in.

Elizabeth 0 votes
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"Are you sure you were on the basemap georeferencing workflow? If you were on the Manual GCP workflow you would not be able to right click on the map to define the point. "

Bingo! That was my mistake. Thanks for the help and your time.

Luis Martinez 0 votes
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