... effects.¹

In Noordam's note, $\vec{\cal V}\,$ is called $\Sigma$ and is mistakenly called a matrix. It actually is a visibility vector.

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... observations²

Note that the matrix C_i denotes the nominal feed configuration and thus does not need to be estimated

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... source³

I note that for an extended source, one might wish to use a different approximation for the inverse Hessian

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