RF Lenses...What's Missing??

[Fast Glass]

And yes, you have been wanting a 600mm f/4 DO for a long time Joel.

But I can't blame ya, I may be snapping up the 400mm f/4 DO myself, still thinking it over. I'm sure a 600mm DO would be a KILLER lens.

A 600mm f/5.6 or 6.3 like my old Minolta 600mm would be killer as well. I like to believe that my posts were heard by Sigma when they made their 150-600mm f/6.3. But who knows. Probably not. LOL.

Or an RF 600mm f/5.6 DO IS, now that would be the ultimate compact and lightweight birding lens. I'd be all over that.