Why are my Co-Ordinates from ECW file coming up at a different position on BricsCAD

domlaterza

We took the images from a drone where we imported to Pix4Dmapper to input our GCP's and export our orthomosaic & DSM as .tif files to import to global mapper which we then exported as an ecw file because exporting a jpg was not possible without decreasing photo quality but when we cross reference our data taken from the ground it does not match to the orthomosaic image even though the Co-Ordinates seem to be in the right position from Global Mapper and from the ground is there any reason for this small shift and how to fix it.

Any help is much appreciated,

Thank you

Johno

Likely a CRS mismatch, double check that your Pix4Dmapper, GM Projection & Datum and the BricsCAD Coordinate Reference Systems are all set consistently as that does not appear to be the case here and the coordinates would be interpreted differently.

I would be working in and exporting UTM from GM to minimize potential issues with BricsCAD.

domlaterza

Yes all my coordinate reference systems are set to the same datum i dont know why it wont match up would seeing my process report from pix4dmapper give you an idea?

Johno

Not familiar with either Pix4Dmapper or BricsCAD but the report may give a clue.

I've located your historic estate in Google Earth and presume then in GM for your geo you have selected IRENET95 (and not Irish Grid)?

If you wanted I could look more closely at your data layers from the GM end, just message me.

domlaterza

Yeah my datum is set to IRENET

What do you mean by data layers?

Johno

By data layers I mean the separate data you are layering, e.g. the .tif (and if it's not GeoTIFF then also it's world & .prj files), and the vector data (blue & red lines) you are layering over it. At least sample sections over the area you are displaying in the images above.