Originally posted by normhead Hirakawa's motives are clearly defined in his technical notes.
I meant to ask northcoastgreg how he knows about what Hirakawa had in mind specifically for the DA* 55/1.4.
There is no dispute about the 43/1.9 and the 77/1.8 having been designed with aesthetics in mind. Extrapolating the same design goals to the DA* 55/1.4 is just speculation.
Given that the DA* 55/1.4 measures really well, but has far less appealing bokeh than say the FA 77/1.8, I'm wondering whether Hirakawa tried to stick to the philosophy he applied to his earlier creations.
Originally posted by normhead To me the 18-135 is the 31ltd of zooms…
To each their own.
That lens is just too poor a performer at the long end to get become even a candidate, AFAIC.
The best contender for that title I know of would have to be the Sigma 18-35/1.8.
Originally posted by normhead Uncompromising when possible, sharp centre and soft edges when trade offs are required by design constrictions, as to tends not to be the case with manufactures like Sigma, who seem to go for a less centre sharp, but more consistent edge to edge philosophy.
Sigma produces so many lenses with different design goals that it is impossible to make such generalisations.
The Sigma 30/1.4, for instance, has excellent centre sharpness but gets quite a bit weaker towards the edges. It is often criticised for being so "inconsistent" and it is by far not the only Sigma lens with that characteristic.