New to Pix4D. I’ve processed a dual grid mission (850 photos) and was planning to then import the orthomosaic into ArcGIS Pro to do some mapping tasks. The full orthomosaic is of terrible quality (whereas previous images created from smaller missions/MME/ArcGIS Pro have been great). If I load individual tiles instead they look better once I reset the bands and stretch method, but how can I export these as a useable geotiff for photo interpretation and mapping purposes? Will appreciate any pointers to help files or tips from others who do this regularly. Thanks, Phil.
Your “terrible quality” orthophoto - Does it also look terrible when you view it inside of Pix4d (“mosaic editor”)? If it looks good in Pix4d but not in Arc, it’s probably your resampling & pyramid settings for import in Arc. This is a common question that pops up when I give some ESRI users an ortho.
If it also looks terrible in Pix4d, we’d need some more info and examples to make a guess. Just based off what you posted here, the dual-grid mission may be your problem. Most of the flight apps are set up to collect dual grid/crosshatch grids with off-nadir imagery (like -65degree camera angle). This is great for creation 3d point clouds that include building facades, but it has a negative impact on the quality of the orthophoto, which will have a much cleaner appearance from NADIR imagery.
Thanks. I will do the software comparison you suggest. I’m pretty sure the second pass in the dual grid was also at -90 (set up in Drone Deploy), but I’ll also try processing just the first pass and see if the result is better…If you have suggestions on what to change in the Arc Pyramid and resampling settings, I’d love to know that as well
Honestly, I don’t remember the settings and I don’t have the PDF that I made as a reference anymore.
Just from memory, I believe that enabling anti-aliasing and turning on bicubic interpolation when building pyramids (to max level…25?) were the main settings. The difficult part was always finding where to change those settings that get used automatically on import.
Hi,
Thank you for your question and thank you Derrick for helping to answer.
Yes, the full orthomosaic is just a merged version of all the single tiles. If there are fine, then also the full orthomosaic should be.
I suggest you check online resources to verify how to re-build the pyramids in ArcGIS pro.
Please let us know how it goes.
Thank you both. I re-processed the images, using only the first half of my dual grid mission, and also changed the camera optimization settings to “All Prior” in the Processing Options (as another thread had recommended as a response to getting a Camera Optimization warning in the Quality report).
THis result seems much better both in the Mosaic Editor and when loaded in ArcGIS as the full mosaic (and I’ve been able to work with it in ArcGIS which is what I need to do (the tiles had been fine earlier, but very slow to load). The Camera Optimization report is now also reassuring rather than concerning. So, I have not tried to figure out how.where to address the ArcGIS Pyramid settings as that does not seem to have actually been the problem (or not the only problem). I will note, though, that images dominated by moderate density sage brush do tend to have quite a pixelated quality to them due apparently to the nature of that landcover.
In the future, I won’t attempt to use a dual grid (Drone Deploy) to improve the image quality, which is what I’d been testing.as it had the opposite effect as Derrick observed.