Yashica f1.9/50mm on Olympus E-P1 - samples and questions

Bought the lens on eBay for US$25 total. A C/Y mount to m4/3 adapter, also via eBay, cost a few dollars more than the lens (it was cheaper overseas, but I did not want to wait for international shipment).

Questions and info below the samples.

Stairway in a park


Little waterfall


Trees over temple

Observations and questions:

Exposure compensation often needs a boost of +0.3, +0.7 or even +1 stop. The base EC will show neither shadow nor highlight clipping in post-shot review, so ... boost EC, take another shot, and repeat until clipping is reported. Yashica raw files usually have a narrow dynamic range. It can often be expanded gracefully. Sometimes, though, a slight stretch of the HSL-L or HSV-V curves turns a blue sky to an awful magenta.

Manual focus has been covered in many posts. My biggest challenge is to focus at "near infinity:" more than about 10 meters but less than perhaps 100 meters.

The lens was an item in the Yashica DSB line, which commentators say was Yashica's consumer quality lens, below professional quality. The aperture diaphragm has six blades. How do you judge the image quality of the samples?

The colors (or transitions from one color to another?) are often richer than the Olympus 17mm pancake provides.

The resolution is not as sharp as good modern lenses. (However, my casual impression is that the Olympus 14-42 zoom lens is softer at the 42 mm end than the Yashica lens.) The question is whether resolution decays smoothly. Looking at the landscape in the samples, what do you think?

Is this correct?: A good but not great modern lens typically has sharp resolution but looks artificial (something about the color transitions), while by comparison a good but not great older lens like the Yashica has fine colors, is somewhat fuzzy, but does not have that too-crisp articial look

More or less the same question: Do computer-designed lenses today have shortcomings that the older lenses do not have? Are most lenses today designed for resolution on Bayer sensors, giving up on smoothness and texture?