The linked open access paper can be found here[1] and is fairly accessible. In section 3 it contains a description of the VLBI technique used by the Event Hori

The linked open access paper can be found here[1] and is fairly accessible. In section 3 it contains a description of the VLBI technique used by the Event Horizon Telescope and the algorithms used to process the data. The methods rely on deconvolution[2] which behave nicely when dealing with pure signals, but can be tricky in practice on noisy data. [1]: https://academic.oup.com/mnras/article/534/4/3237/7660988 https://academic.oup.com/mnras/article/534/4/3237/7660988 [2]: https://en.wikipedia.org/wiki/Deconvolution https://en.wikipedia.org/wiki/Deconvolution