Dear gang,
It seems that ConTeXt does not currently implement optical scaling for Latin Modern -- at least not by default. For example:
=======
\startTEXpage[offset=1em]
Test {\tfa Test} {\tfb Test} {\tfc Test} {\tfd Test} {\tfx Test} {\tfxx Test}
\stopTEXpage
=======
In the log we have
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mkiv lua stats > loaded fonts: 2 files: latinmodern-math.otf, lmroman10-regular.otf
=======
Is this behavior intentional? The needed sizes are certainly available (/texmf/fonts/data/gust/lm).
This issue came up while trying to test/implement something else. Although Computer Modern / Latin Modern is perhaps hardly popular for contemporary publication work, a full implementation of the full palette of optical sizes is still useful as a benchmark,
etc.
Best wishes
Idris