For grids not aligned with the scan axes, we rotate them and calculate the microns per pixel in the rotated image along the rows and columns. This is fine for square (or almost square) images and those where the grid is very closely to aligned with the scan axes in the first place. However, results will be inaccurate if this is not the case. i.e. If your image is scaled very differently across the rows and columns and the grid wasn't imaged in an orientation close that of the scan axes then you will get inaccurate values.
We could modify Grid2MicsPerPixe to calculate the microns per pixel along the scan axes, taking into account the grid rotation. So far this has not been needed so it hasn't been implemented.
For grids not aligned with the scan axes, we rotate them and calculate the microns per pixel in the rotated image along the rows and columns. This is fine for square (or almost square) images and those where the grid is very closely to aligned with the scan axes in the first place. However, results will be inaccurate if this is not the case. i.e. If your image is scaled very differently across the rows and columns and the grid wasn't imaged in an orientation close that of the scan axes then you will get inaccurate values.
We could modify Grid2MicsPerPixe to calculate the microns per pixel along the scan axes, taking into account the grid rotation. So far this has not been needed so it hasn't been implemented.