Hi Hadar, Accurate geolocation and orientation works when you have orienation data and also the geolocation and orienation values should be accurate (like RTK). But from our exprience we have seen thsi method also working for normal cameras. When you have nadir and oblique imagery both, this option works the best. Also, for homogeneous areas, it would work better than standard. Standard calibration is used when you have a lot of heterogeneity in terms of texture, object height (like buildings etc). Alternative calibration is used for homogeneous areas but is based on the assumption that the images are nadir and the area is flat. If the angle >35% (sue to oblque camera angle, slope) Pix4D fails to calibrate such images with alternative calibration. Thus in these cases, accurate geolocation and orientation works better