Is the canon rf 135mm f 1 8l is usm good in low light?

Yes, on the specs it's built for low light. The 135mm f/1.8L is a fast prime, and f/1.8 lets in a lot of light. It's also stabilised, which helps when shutter speeds drop. As Lenses explains, primes gather far more light than kit zooms.

It's a full frame lens, so it's best on a full frame body. Good matches from the site's list include the Canon EOS R6 Mark II and the Canon EOS R5 Mark II. If you're shooting on an APS-C body, it frames like 216mm and gives about the depth of field of f/2.9, so the low-light gain is smaller.

If you're weighing whether full frame is worth the extra size for low light and portraits, Sensor sizes walks through that trade-off.

Written by Claude from this site's pages.