Hepos/GGRS87/TM87 added in ReachView3 v. 6.3

Emlid Flow & Emlid Flow 360
11

Hi Evangelos,

Thanks for the clarifications!

Each country has its own rules on the coordinate systems, and it’s always big detective work to get down to them.

I’ve just discussed this case with our GIS developers, as it seemed suspicious to me. And it’s indeed happened to be a tricky one — and consistent with your comment.

At the moment, we have 2 different GGRS87 datums in ReachView 3: GGRS87 and GGRS87 Approx.

  • GGRS87 Approx datum is the target datum we got after 7-parameters Helmert transformation
  • GGRS87 datum is the target datum on which both Helmert transformation and HEPOS horizontal grid applied

We initially thought that, in most cases, our users would need to work with the datum after the grid application. So, to work with the target datum without the HEPOS grid, you can choose GGRS87 Approx in ReachView 3.

Looks like the current naming is misleading. We’ll work on making it more precise.

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