Sony Alpha 55 SLT, 50/1.4 focused using LV at f/1.4 and shot at f/5.6 at 2.00 m from focal plane. Could it be it has only one layer of OLP filters?
Thanks for participating, it will also help others.
It doesn't look like a single OLPF layer, that would cause a more elliptic blur. It is probably a slightly less effective OLPF filter, or the Raw converter is trying too hard. Normally the diagonal directions have a slightly higher resolution compared to the horizontal/vertical directions. That's normal in square grid.
I think the sharpening radius was a tad too large, causing some halos that interact with the lower frequencies outside the 92 pixel Nyquist boundary. There is also a beginning of mazing artifacts near Nyquist, similar to what I can get with Capture One as Raw converter. Which Raw converter did you use?
Since defocus will quickly kill resolution near Nyquist, I usually take several images, Live View with loupe, and pick the best. It will teach us how important technique, and things like Live View are for the best quality.
Of course this is not a contest, but Bill's micro lens is very good, and will be a challenge for other lenses to reach so close to Nyquist. Your lens looks pretty normal (as you'll see when others participate), just check your sharpening settings or try a different Raw converter or different settings (e.g. no clarity, noise reduction, and such).