Testing manual focusing accuracy again. Focus was on the left Mandarin Duck and very nice ducks they are. In recent years I'm certain that the population of these very colourful ducks has increased dramatically. As I was shooting on this day, I saw at least 20 of these all together in a relatively small area. Never seen that before.

Anyway, I digress, as you can see the lens is very sharp even wide open as in the image above.