Forum

Author Topic: Possibly Wrong conversion in EPSG 5513  (Read 1873 times)

Phogi

  • Jr. Member
  • **
  • Posts: 99
    • View Profile
Possibly Wrong conversion in EPSG 5513
« on: August 25, 2020, 02:55:25 AM »
Hi Alexey,

I found some post before regarding EPSG 5513 / 5514 support, which is great, however when I am converting GCPs from WGS84 to EPSG:5513 and 5514 they show different sign (positive vs negative), but in EPSG.io they are the same: https://epsg.io/transform#s_srs=5513&t_srs=5514&x=-527358.6200000&y=-1140103.1800000

Which one is correct? By checking the proj4 string definition they are exactly the same in Metashape, so why there's a different sign for output? I know there's SW vs NE axis but not sure which source is correct.

Hope to hear from you soon.

Best,

Alexey Pasumansky

  • Agisoft Technical Support
  • Hero Member
  • *****
  • Posts: 14813
    • View Profile
Re: Possibly Wrong conversion in EPSG 5513
« Reply #1 on: August 27, 2020, 07:28:31 PM »
Hello Phogi,

As far as I understand, Northing and Easting values for 5514 (Krovak North) should be negative, whereas Southing and Westing for 5513 (Krovak) should be positive.

Please check page 30 of the following document:
https://www.iogp.org/wp-content/uploads/2019/09/373-07-02.pdf
Best regards,
Alexey Pasumansky,
Agisoft LLC

Phogi

  • Jr. Member
  • **
  • Posts: 99
    • View Profile
Re: Possibly Wrong conversion in EPSG 5513
« Reply #2 on: August 28, 2020, 12:33:35 PM »
Thank you Alexey, it seems that's some issue with gdal or epsg.io, much appreciate for the details!!