The Low Light Full Frame Myth: Canon EOS R vs GH5s

Camera Conspiracies debunks the low light myth:

They say full frame cameras are better in low light than crop sensor cameras. Micro four losers especially. Today we find out if that was just a myth by pitting the full frame Canon EOS R against micro four thirds Panasonic GH5s. Which is cleaner at higher iso’s? Does the GH5s have better autofocus? Who has more Toneh?!