In article ,
RichA wrote:

Brilliant! Likely very cheap, going the opposite direction from ridiculous
f4 speed long lenses. We were arguing about this the other day on dpreview.
However, no IBIS/OS, no deal at those focal lenghts.

read it again.

https://petapixel.com/2020/07/06/her...w-rf-600mm-f-1
1-and-800mm-f-11-lenses/

According to Noki****a, both lenses feature a DO element (to keep the
size down), and between 4 and 5 stops of image stabilization

one major problem is that f/8 and certainly f/11 is above what the
camera's autofocus system can handle, so what people will end up
getting are stable, but blurry photos.

also, do lenses have a higher propensity to flare.