When you've got an f/4 lens, it's not hard to avoid mechanical vignetting and the resultant cat's eye bokeh. Fuji almost did that with the GFX 100 RF. I think they would have if they weren't trying so hard to make the lens small. These are a bunch of far out of focus images of a distant point source at f/4 and 1/1000 second.

Let's zoom in on the lower right quadrant.

Yep, there's the tell-tale sign of a fast leaf shutter. Not that fast in this case: I used 1/1000 second for these images.
If you use this lens at high shutter speeds, you're going to have to make your peace with this.
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blog.kasson.com

Let's zoom in on the lower right quadrant.

Yep, there's the tell-tale sign of a fast leaf shutter. Not that fast in this case: I used 1/1000 second for these images.
If you use this lens at high shutter speeds, you're going to have to make your peace with this.
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the last word the last word - Photography meets digital computer technology. Photography wins -- most of the time.
Photography meets digital computer technology. Photography wins -- most of the time.
blog.kasson.com