“This is in many ways an optically perfect lens. The Blue Spectrum Refractive Optics (BR) and UD element with Air Sphere Coating (ASC) and Fluorine additions produces sharp results in every situation. The Auto Focus is notably faster than the original EF version - but the new RF lens has superb reliability at f/1.2 with no noticeable aberrations. The bokeh in the defocused backgrounds is as reputable as that produced by its EF predecessors: just Beautiful.
I bought this lens for Astrophotography with the EOS Ra rather than portraits with other R cameras, but it performs exceptionally well in every application. The BR optics produce jawdropping results with sharp stars and no observable coma, even at f/1.2. I can capture nebulous regions of the Milky Way with this lens that are devoid of the color blooming and CA that shows up with the older EF f/1.2L lenses. And a single 6-second exposure of the Carina Nebula in JPEG at f/1.4 matched stacked shots taken by professional Observatories located on dark-sky mountaintops. This is a fairly large lens. It's also fairly heavy. But this is the most surprising and impressive lens I've used in over 25 years. (Purchased by me from George's Sydney store in mid-2020)”
