GCP Editor Pro EPSG entry

[barry]

I just bought the GCP Editor Pro and I’m trying to create my first one. I’m sure I’m doing something wrong but I can’t seem to get the correct value (at least I think it is the correct value) into the EPSG box.

I set up the lines for each of my GCPs and the “Go to next step” box is available.

By default the EPSG/PROJ box has EPSG:4326. But the area I am in the EPSG code (at least according to Propeller) should be 6319. If I type EPSG:6319 into that box, the “go to next step” box becomes greyed out.

Here is the information the Propeller output provides to me for that:

Geographic coordinate reference system	NAD83(2011)
Geographic EPSG code	6319
Projected coordinate reference system	NAD83(2011) / New Jersey (ftUS)
Projected EPSG code	6527
Vertical coordinate reference system	NAVD88 height
Vertical EPSG code	5703
Geoid model	geoid12b

Can someone tell me how I get the right code into that box?

Sorry if I am missing something obvious here.

Thank you

[APOS80]

Try a proj4 string instead.

EPSG can be a problem sometimes

[barry]

Thanks. I tried “PROJ:6527” but have the same problem - the button is greyed out.

[APOS80]

That’s not a correct proj4 string.

[barry]

Understood. But I am using the GCP editor to make my life easier (in theory) and none of the values that I have available seem to work in that field.

The documentation talks about what to put into the text file. The whole point of this software (I believe) is to help create the text file. According to the system I’m using (Propeller) the Geographic EPSG Code is 6319. That code shows up as valid in EPSG.IO (which is where the app takes you) but can’t apparently be entered.

If I enter just the number “4326” (which is WGS84) into that field then the button to proceed is available. If I enter “6319” the button goes away.

So…any thoughts on where we go from here to get a valid code into that field?

Should I just accept 4326 and then edit the text file afterwards and enter the real code? That seems not to be the right step as the next step is to tie in the photos to the locations and I don’t know if that would be valid if the reference system isn’t correct in that step.

Obviously, I am still very new to all this and going through a steep learning curve, but this doesn’t seem like it should be that hard.

Thanks for the input.

[APOS80]

Try this string:

+proj=longlat +ellps=GRS80 +no_defs +type=crs

You can get them here:

EPSG.io: Coordinate Systems Worldwide

[barry]

OK - to finish up.

It seems that the easy way to do this is to convert to the PROJ code and just use that. I wasn’t sure how to do that but now see that if I go into the EPSG.IO site linked, enter the code, click into it and (importantly) scroll all the way down it gives the proj string.

Thanks very much to @APOS80 for getting me started in the right direction.

It would be nice if the EPSG codes were supported out of the box but, given this workaround, there are probably more pressing development items.

Thanks for all the help as always!

[APOS80]

If you look at the page for your EPSG code the proj.4 string is down below among other ways of representing your projection.

If that doesn’t work then you can always geo reference in post with Qgis(ortofoto/dsm) or CloudCompare(pointcloud).

[barry]

Thanks APOS80 - I didn’t scroll down far enough to see that. Mea Culpa on that

[luc23]

An additional way to get PROJ4 code is with project open in QGIS there is a button bottom right of screen with your currently selected EPSG.

If you click it should open a window, and if you scroll down in that window you can see PROJ4 code for whichever EPSG is currently highlighted.