Patent: Canon RF 300mm f/2.8L IS 1.4x plus other supertelephoto optical designs | Canon Rumors

Copying Nikon but in the best way possible. Flick in 1.4x TC are the best value add to the mirrorless big lenses and makes TC’s much more usable and available in fleeting moments.

I really want to see the first generation of big whites for the RF system, I have high hopes Canon put in the effort after the assuredly poor reception of the adapted EF/built in 2X TC lenses.

300mm f/2.8 was one of my favourite lenses for a decade, though I have since moved on to 400 and 800 as preferred focal lengths. I would however love a 120-300f/2.8 TC to take along with a 400 f/2.8 TC or shove them both into one monster 100/200-400 f/2.8 TC.