= Solution
During recollapse $H<0$, so nearby comoving galaxies are increasingly blueshifted rather than redshifted. Their physical separations and angular-diameter distances shrink, making them appear larger and generally brighter; in a closed geometry sufficiently old light can also produce repeated or strongly focused images.
The <Cosmic microwave background anisotropy>[cosmic microwave background] temperature obeys $T_\gamma\propto a^{-1}$. It therefore rises without bound as $\theta\to2\pi$, and its photons are blueshifted. Before the formal <Big Crunch>, the growing temperature reionizes matter, scattering makes the universe opaque, and the idealization that old galaxies and the original last-scattering surface remain directly visible eventually fails.
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