editorsteve wrote:
I have the Tamron-badged Pentax FA version and use it on a full-frame K1. I think it is a generation behind the new Sony E version. It is terrific. Not quite as good on the edges at F/2.8 as my wife's Canon 24-70 (used on an R and a 6D) and not as fast-focusing (the FA uses the camera's motor). But smaller, lighter, cheaper. I don't see a difference even at F/4 but the Pentax has more pixels to start with. Both are contrasty, low flare.