Knowledge Test ~ Good Luck!

I thought it'd be fun to see if anyone can figure this out.  It's a game of sorts.  Which lens took which photo?

Have a look at this and tell me what you see and what you think.  The images on the right are of the entire scene downsized to 1500 pixels.  The images on the left are 100 percent crops of the fish in the images on the right.  

It won't matter in this test, but I used a very low mileage Sony A7 (first generation) camera with the ISO set to 64, and strapped it to a very sturdy tripod.

 

 

I deliberately chose two lenses of the same focal length and which showed differences in image rendition under test.

To help things along, I'll give a few hints. 

The setup was chosen pointing toward bright, soft light so as to express a full range of tones with plenty of detail in the shadows and specular highlights bouncing off unpolished metal.

One lens was designed in the very early 1960's and the other lens is quite current.  Both derive from the same base optical layout.   

One lens is single coated and the other is multi-coated.

One has a tiny bit of fungus around the very outer edges of the forward element and the other is clean and clear.  

Both RAW images were exposed and processed with exactly the same parameters on a Linux system using RawTherapee.  

Lastly, one lens was designed with over-corrected spherical aberration behind the point of focus and the other was designed with under-corrected spherical aberration behind the point of focus.

NOTE: I think this illustrates that the optical layout (ie: Tessar, Planar, etc) has little to do with rendition.  It's the math used on each and every surface in any design that determines the curve/shape of the lens that matters. 

Still, this is difficult, isn't it?

I've looked at the two images for quite awhile and know where the obvious differences are.  Of course knowing the answers helps me know where to look.

Yet this raises, for me, one simple question: Are the differences important enough to choose one lens over the other?

Last thing: If you correctly tell me just one lens, I'll buy you a couple beers at my favorite pub after the 19th of May, 2021 when things start to re-open here in Paris.