Bug report #2385

Italian Sardinia custom proj is wrong

Added by Luca Casagrande almost 11 years ago. Updated over 10 years ago.

Status:Closed
Priority:Low
Assignee:Tim Sutton
Category:Projection Support
Affected QGIS version: Regression?:No
Operating System:Debian Easy fix?:No
Pull Request or Patch supplied: Resolution:fixed
Crashes QGIS or corrupts data: Copied to github as #:12445

Description

Hello folks,
the proj string for custom Italian Sardinia projection is wrong because it has got 2 towgs84 setting.

The right one is this:

+proj=tmerc +lat_0=0 +lon_0=9 +k=0.9996 +x_0=1500000 +y_0=0 +ellps=intl +units=m +towgs84=-168.6,-34.0,38.6,-0.374,-0.679,-1.379,-9.48 +no_defs

I think that would be better to add GB Roma40 to the name of each custom projections.

Thanks

Luca

italian_srs.sql (593 Bytes) Niccolo Rigacci, 2010-04-06 10:44 AM

History

#1 Updated by Tim Sutton almost 11 years ago

  • Resolution set to fixed
  • Status changed from Open to Closed

d8988cce (SVN r12822) implements these updates. For the record:

update tbl_srs set description = description || ' GB Roma40' where srs_id > 3639;
update tbl_srs set parameters='+proj=tmerc +lat_0=0 +lon_0=9 +k=0.9996 +x_0=1500000 +y_0=0 +ellps=intl +units=m +towgs84=-168.6,-34.0,38.6,-0.374,-0.679,-1.379,-9.48 +no_defs' where srs_id=3643;

#2 Updated by Luca Casagrande almost 11 years ago

  • Resolution deleted (fixed)
  • Status changed from Closed to Feedback

I noticed that towgs84 parameters are not right for Italy. According to GRASS those are the right ones:

ROMA40 Fuso 1 Peninsular
+proj=tmerc +lat_0=0 +lon_0=9 +k=0.9996 +x_0=1500000 +y_0=0 +ellps=intl +units=m +towgs84=-104.1,-49.1,-9.9,0.971,-2.917,0.714,-11.68 +no_defs

ROMA40 fuso 2 Peninsular
+proj=tmerc +lat_0=0 +lon_0=15 +k=0.9996 +x_0=2520000 +y_0=0 +ellps=intl +units=m +towgs84=-104. 1,-49.1,-9.9,0.971,-2.917,0.714,-11.68 +no_def

ROMA 40 Sardinia
+proj=tmerc +lat_0=0 +lon_0=9 +k=0.9996 +x_0=1500000 +y_0=0 +ellps=intl +units=m +towgs84=-168.6,-34.0,38.6,-0.374,-0.679,-1.379,-9.48 +no_defs

ROMA 40 Sicily
+proj=tmerc +lat_0=0 +lon_0=9 +k=0.9996 +x_0=1500000 +y_0=0 +ellps=intl +units=m +towgs84=-50.2,-50.4,84.8,-0.690,-2.012,0.459,-28.08 +no_def

#3 Updated by Niccolo Rigacci over 10 years ago

Please note that there are also unwanted spaces as in "-104. 1", etc.

I attach the SQL statements to fix 3 entries in the database (only one is correct).

#4 Updated by Jürgen Fischer over 10 years ago

  • Status changed from Feedback to Closed
  • Resolution set to fixed

applied in . Thanks.

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