New 1.4.0 datum transformation options help

[orellius]

Hello,

I've spent many hours troubleshooting what the heck is going on, I was about to report this as a bug but it might not be so I came here. Might be a new feature, that is just going to bug me!

To start with, I'm no Geomatics Engineer, but I've been working for various geomatics/survey equipment resellers for almost 15 years so have a pretty good understanding, just looking for help.

Been using Photoscan Pro a few years. Ever since before 1.4.0 I could either generate a DEM/ortho in UTM or 3TM inside Agisoft, and view it there, and do GCP checks,  fly my mouse over the ortho and check coordinates/elevations, etc. Then I could export in UTM/3TM and import to other software and everything was just as accurate as it was in Photoscan.

I could also generate DEM/Ortho in WGS84, and at the export stage choose UTM/3TM, and again have no issues importing to other software and it still being in the right place.

Now in the newest build of 1.4.0, I can no longer generate it inside photoscan, in just for this one example, NAD83(CSRS) 12N (EPSG 2956). If I do so, all the data is shifted by up to a meter in XYZ. See screenshot included showing the difference in GCP checkshots compared to the surveyed coordinates. It shows the difference table as well, which is consistent across the board.  Notice though the accuracy Photoscan is reporting for my checkshots and photos, which is good. This has worked fine for years, now it doesnt. If I export this same data in Photoscan 1.3.5 my data is accurate.

I've narrowed it down to something relating to the new export options for datum transformation, but I dont know enough about that part to know what is actually happening. The problem I see is I figured out how to actually export the data properly (only if I generate it in WGS84, then export it). I have to choose an advanced export option (see screenshot). It is defaulting to EPSG:1946 at export which has a shift/rotation. If I choose "none" if gives an error. If I choose EPSG:1842 it has zero shift/rotation and my data is good. This advanced button didnt exist before, now it does and it defaults to something I don't want. On top of that, It seems to be defaulting to this if you generate your data in EPSG:2956 in the software, so it's shifted and rotated in the viewer...so I'm forced to view it in WGS84, then export it elsewhere.

 

• Problem 1 is why does generating in EPSG:2956 (and maybe others?) for viewing INSIDE Photoscan have a new shift/rotation that it did not have before, and how do I stop it from doing that?
• Problem 2 is why is this new version now defaulting to this option at the export phase when going from WGS84 to grid?

It's like my goto option is totally broken now, and my backup plan to do in WGS84 then export elsewhere has an option defaulted that I don't want. Kinda sucks!

Again keep in mind I don't fully understand the new EPSG codes at the export datum transformation option. Honestly it took me hours just to see the new button was there...I hope this is unintentional and will be addressed. I think it should default to what it was before, leave the advanced options for those who want to play with them!