3rd party apps performing better in terms of capturing low light photo,
Night Mode in MIUI Camera just focusing on center part of image & turning side of image mostly dark,
plus there's lots of noise & grain on image too,
on the other hand 3rd party apps like GCam performs better with even in extreme dark situation,
it captures the detail from every aspect & image comes out more soft & less noisy/grainy,
here's two simple image I capture from my Redmi Note 9 Pro Max:

Captured using MIUI Camera App using Night Mode:


Captured using GCam App using Auto Night Mode:


as changing apps can bring this bigger change,
I hope developers would do something to improve it's quality.

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Device Model: Redmi Note 9 Pro Max (Excalibur)
MIUI Version: 12.0.3.0 (QJXINXM)
MIUI Camera App Version: 4.0
GCAM App Version: 8.1