On 2013–01–09 Hans Hagen wrote:

> the latest beta has this:
> 
> % \enabletrackers[graphics.programs]
> 
> \starttext
> 
>     \externalfigure[cow.pdf][conversion=stripped]
> 
> \stoptext

Nice feature, indeed. It might save a preprocessing step. We
preprocess with

  -dProcessDSCComments=false

otherwise PDFs generated by external programs (OpenOffice, I'm
looking at you) in combination with particular fonts might wreak
havoc with the document they are included into. I don't know which
downsides this might have, though. In our workflow this leads to
more predictable results. Maybe someone with more insight of the PDF
internals could judge if it makes sense to add this option.

It looks like the presets are not hard-coded. What is the interface
to change the presets (screen, ebook, prepress)?

Marco