SUMMARY
The common advice to always keep ISO as low as possible may be outdated for modern mirrorless cameras. Many feature dual-native, dual-gain, or dual-base ISO, which involves two analog circuits. This technology allows for two optimal ISO settings, meaning a higher base ISO can sometimes yield cleaner images than lower, non-base ISOs, while also enabling faster shutter speeds. Manufacturers often under-promote this feature, which is more prevalent in video due to noise reduction complexities. Canon's EOS C400 even introduced triple-base ISO for enhanced noise reduction.
TAKEAWAYS
Modern mirrorless cameras often have dual-native ISO, not just one base ISO.
Dual-native ISO allows for two optimal ISO settings, improving image quality at higher values.
This technology can enable faster shutter speeds without sacrificing image clarity.
Some cameras, like the Canon EOS C400, feature triple-base ISO for even better noise control.