By the way, I incorrectly said: "The real image of a star is an infinitesimal point, so small that if it were not for this scatter on the receiver, we would not have seen it at all." In fact, the pixel will shine, but only one pixel, which opposite the star.
I think it's easier to show what I mean. The left picture below shows how you realize the obscuration of the dark nebula. And in the right picture I showed how it really should happen on astrophoto. Even if the dark nebula is closer than the star. The star is further away, but the glare is closer. The glare is created by the camera lens. It's just light scattered by the optical elements of the lens. The core of the star is very, very small. Less than the pixel size of the photosensitive matrix. For the demonstration, I used your wonderful picture of Fomalhaut.
[attachimg=1]
On the left you can see that the dark nebula is blocking the star's radiance. It's as if the sun was completely blocked by the horizon at sunset (оn the right is the original correct the setting sun picture).
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Dirk, I saw the letter, I want to study it more closely tomorrow.