RTK PPK workflow confusion

Being a newb, I feel like this is bit like using Photoshop or Fusion360. 10 ways to do the same thing but you could spend years doing it wrong lol! So I’m at a mine where the surveyor measures a permanent point we’ll use as the base location. His rover gives us output coordinated, so UTM and HT2 height. Not LLH ellipsoid and no cell service to convert. So no big deal as I’ll just convert the point later to LLH and convert the HT2 height to ellipsoid for Emlid studio stop and go. Figured this was how it would go anyway as I was sure there was no way I’d get corrections on this site. Well, got a fix solution the entire time. A number of times during the day I found cell coverage, I could have done the conversion but what would I do with it? I thought base shift would work so I could use the collect points on site. Read the documentation for baseshift and that’s a no. So am I stuck with using Emlid studio? Stop and go will only give me the LLH and ellipsoid points that aren’t much use in the field. Sure would be cool if emlid studio would also output in the projects output coordinates. Am I missing something obvious?

Are you using Pix4D or Metashape? If then, they both have a handy tool for on-the-go conversion, also including elipsoid to a specified geoid.

I’m using Pix and starting ODM. Didn’t see any tools that would help my base shift lol. As for geoid conversion, I’ll check it out. Last I heard there was no support for adopted models in Canada. Output is WGS84 UTM and CGVD28 HT2 2002V70. I hate using manual ellipsoidal height in Pix. You can be out 2 or 3cm from one end of the scan to another.

Looks like Pixmatic supports HT2, but not Pixmapper…

Hi Shaun,

Surveying is an art :sweat_smile:

So, your main question is how to convert local coordinates to LLH, right? Judging by the vertical datum you use, you’re from Canada. I know there are official conversion tools from NRCAN: GPS-H and TRX. Maybe one of them helps you.

As I see, you don’t need a base shift in your setup.

And in case you’ll decide to work with Stop&Go, there is a trick you should like:

  1. Download corrected CSV from Stop&Go. It contains geographic coordinates in the datum of your base
  2. Create a project in ReachView 3 in a local projection based on the same datum
  3. Import Stop&Go CSV into this project and export it again. It should contain projected coordinates

Get out! That’s super cool. Thanks!

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