The phrase high-resolution imaging is used in astronomy, generally meaning "better angular resolution than what we normally get", the actual resolution-range intended varying according to the subfield's usual practice and tools. The highest resolution is generally achieved using interferometry with the longest baselines combined with the shortest wavelengths, i.e., very-long-baseline interferometry with millimeter waves, such as the Event Horizon Telescope, for which 60-micro-arcsecond resolution has been cited. Sub-micro-arcsecond resolution is now a general goal within astronomy.
Increasing resolution is generally achieved through larger apertures, with speckle suppression techniques including PSF fitting, lucky imaging, and adaptive optics, with space telescopes to escape seeing issues, and with interferometry, as above as well as including space telescopes to create even longer baselines, and with optical interferometry. Specialized techniques have also been considered and used for very high resolution, one general notion being the use of astronomical objects to assist in viewing others, including: