At night on a volcano summit, six telescopes stare at the same speck of light. Each catches its own copy of the wave, and if you combine their signals, you get an image that no single instrument could produce alone. But there's a catch: light captured by different stations cannot simply be added like photographs. It must be measured, and the measurement method determines how sharp the final picture will be.

Until now, telescope networks have operated like an orchestra without a conductor. Each instrument played its own part, and then the recordings were aligned on paper. This approach suffers from a fundamental incompatibility: estimates of different parameters interfere with each other, and sensitivity drops as the number of stations grows. The authors of the new study asked: what if the musicians were given a joint rehearsal?

It turns out that joint processing of copies removes the incompatibility penalty. Instead of measuring each copy separately and averaging the results, one can coherently mix them and measure all at once. The sensitivity gain grows as the square root of the number of stations: for six telescopes, this is almost two and a half times. A numerical example for four stations showed a reduction in error risk from 144 to 84 arbitrary units already with two copies.

Simulations for an array in Hawaii confirmed that collective measurement improves image correlation from 0.686 to 0.810. For quasar 3C 273, the required baseline shrinks from 1390 kilometers to 256, that is, by a factor of 5.4. This means that future telescope networks could obtain the same images while being several times more compact.

An orchestra that rehearses together hears every note more precisely. Likewise, a telescope network that measures light collectively sees farther and sharper than the sum of its parts. The curse of incompatibility is lifted, and astronomy opens a path to imaging the vicinity of black holes and distant quasars with quantum precision.