OK, attached are two non-scientific snapshots of my office banana tree
I set the aperture at f/2.0 and I turned the focus ring to the closest distance of 1.1m.
Although the booklet accompanying the lens states clearly that the DC feature should be used according to the aperture set on the lens, I dismissed it and DCed to the maximum position. This is the first time I didn't follow the set rules
What I immediately noticed was that the focus distance changes as you rotate the DC ring.
In other words you can get closer with the DC ring at Rear and you need to move backwards if you rotate the DC ring to Front.
So even I had tried a scientific approach and put the camera on a tripod, I would have had difficulty performing the test at the closest distance from the subject
Another thing that I noticed was that I am steadily falling in love with this lens and it's creamy bokeh
The two photos attached depict the DC ring set to R and F at the nearest focus distance and at F/2.0.
To be continued...