[PROJ] World UTM in a proper datum

[Javier Jimenez Shaw]

Hi Noel,
If I am the only user of the data, I can do that (and whatever I want). But
if I have to produce accurate data processed by somebody else, I fall into
the hole of vagueness of WGS84. For instance, if I create a precise GeoTIFF
and I want to tag it with an EPSG, using EPSG:326XX is... vague. Or a GCP,
or anything else. There are several alternatives for the geographic crs.
I know I can apply UTM over ITRF2014 (GDAL does it easily). But there is no
EPSG code for that.

.___ ._ ..._ .. . ._.  .___ .. __ . _. . __..  ... .... ._ .__
Entre dos pensamientos racionales
hay infinitos pensamientos irracionales.



On Sat, 17 Apr 2021 at 22:24, Noel Zinn (cc) <ndzinn at comcast.net> wrote:

> Unlike an empirically-derived datum transformation (e.g. WGS <> ITRF),
> which can have different levels of "accuracy" depending how it was derived,
> a map projection (lat/lon <> N/E) is defined mathematically and is precise,
> i.e. without error.  Having said that, there are better and worse
> algorithms for UTM, but that's not the question you're asking.  In a
> datum transformation sense UTM will always be as (and only as) "accurate"
> as the geographicals you convert to N/E.  So, use EPSG:326XX and
> EPSG327XX, but plug in your precise geographicals.
>
> *From:* Javier Jimenez Shaw <j1 at jimenezshaw.com>
> *Sent:* Saturday, April 17, 2021 2:44 PM
> *To:* proj <PROJ at lists.osgeo.org>
> *Subject:* [PROJ] World UTM in a proper datum
>
> Hi
>
> Maybe there is a better place to talk about this, but I do not know which
> one. I hope somebody from EPSG is reading this, and may give me a clue.
>
> We have talked many times about the lack of accuracy of WGS84 (EPSG:4326),
> the datum ensemble, etc.
> The problem is that I miss an accurate equivalent of the projected family
> "WGS84 / UTM zone XXY"(EPSG:326XX and EPSG327XX) for XX between 1 and 60
> and Y is N or S. It would be nice something similar (a worldwide projected
> CRSs on UTM), but over a proper accurate and well defined geographic CRS
> (ITRF2014, WGS84(G1762), etc).
>
> Do you know if there is any plan? Or do they exist and I was not able to
> find them?
>
> Thanks.
> .___ ._ ..._ .. . ._.  .___ .. __ . _. . __..  ... .... ._ .__
> Entre dos pensamientos racionales
> hay infinitos pensamientos irracionales.
>
> ------------------------------
> _______________________________________________
> PROJ mailing list
> PROJ at lists.osgeo.org
> https://lists.osgeo.org/mailman/listinfo/proj
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/proj/attachments/20210417/7f7d2ad4/attachment.html>