Well with
\definefontfamily[mainface][serif][Minion Pro][opticalsize=yes]

It does work. But I just wonder why some people could omit this option? Is there a bug?

Will this be omitted in later distributions?

Results has been attached, 4 complete build result for you to analyze.

南京大学现代工程与应用科学学院 2013级

罗晨星
Luo Chenxing
—————————————
chenxing.luo@gmail.com

2014-03-10 10:23 GMT+08:00 Wolfgang Schuster <schuster.wolfgang@gmail.com>:

Am 10.03.2014 um 02:05 schrieb Wolfgang Schuster <schuster.wolfgang@gmail.com>:

> Hi,
>
> can you run the attached file and show me the resulting pdf file?

Can you also try what happens when you enable optical sizes!

\definefontfamily[mainface][serif][Minion Pro][opticalsize=yes]

\setupbodyfont[mainface]

\starttext
Hello World!
\stoptext

Wolfgang