Which techniques are used to mitigate distortions caused by atmospheric turbulence ('seeing')?

Speckle interferometry or adaptive optics

Atmospheric turbulence creates significant blurring and smearing of stellar images, hindering precise positional measurements from the ground. To counteract these dynamic distortions, advanced computational techniques are employed. Speckle interferometry processes many short-exposure images to reconstruct a better image, while adaptive optics systems rapidly adjust deformable mirrors in real-time to compensate for atmospheric path length changes. However, these methods are complex and often specialized, and even with their use, the instability of the path length makes simultaneous relative measurements over large angular separations exceptionally challenging.