Forum

Author Topic: What is the best way to align photos with GCP?  (Read 3713 times)

Decks

  • Newbie
  • *
  • Posts: 15
    • View Profile
What is the best way to align photos with GCP?
« on: May 27, 2019, 02:12:47 PM »
What is the best way to align photos with GCP?

1 - Align in the low, insert the GCP, deselect the photos and select only the GCP and align again in the high.

2 - Align in high, insert the GCP, unselect the photos and optimize.

3 - Align at high, insert GCP and optimize alignment with selected cameras and GCP.

Ps: Drone without RTK, and GCP with RTK

JMR

  • Hero Member
  • *****
  • Posts: 505
    • View Profile
Re: What is the best way to align photos with GCP?
« Reply #1 on: May 27, 2019, 07:31:52 PM »
Although 2 is strictly right, 3 works perfecly well in the very most of cases, unless your GCPs are very badly distributed and/or they are in a coordinates system that is incompatible with that of the cameras (that is the case when GCP are in a local system with totally diferent numbers than camera centers).
Normally, enabling/disabling cameras does not make any diference in EO but after the third decimal place (sub mm). Well that is assuming that accuracy settings are left as default by 0.005m for GCP and  10m for cameras.
Best regards
GEOBIT

PD. re-align is pointless in my opinion.

Decks

  • Newbie
  • *
  • Posts: 15
    • View Profile
Re: What is the best way to align photos with GCP?
« Reply #2 on: May 27, 2019, 11:42:26 PM »
tks dor reply!

if my GPS has 0.2 m accuracy (example), I need to insert this into the "marker accuuracy"? what is marker accuracy (pix) and tie point accuracy (pix)? (I could not find it in the manual)

phomzaDPS

  • Newbie
  • *
  • Posts: 1
    • View Profile
Re: What is the best way to align photos with GCP?
« Reply #3 on: March 07, 2022, 01:59:46 PM »
Good day, I m new user of agisoft and I had challenges with my final DEM, the model seems good close to GCPs, but when I move away from GCPs there is a discrepancy that I don’t understand when checked against othe check points. Please advise