\starttext

\defineexternalfigure[test][width=2cm]

\defineexternalfigure[less][test][width=3cm,background=color,backgroundcolor=green]
\setupexternalfigure [less][height=.5cm]

\externalfigure[cow.pdf][test] \par
\externalfigure[cow.pdf][test][frame=on] \par

\useexternalfigure[test][cow.pdf][width=2cm]
\useexternalfigure[more][][test][background=color,backgroundcolor=blue]

\externalfigure[test] \par
\externalfigure[test][frame=on] \par
\externalfigure[test][width=4cm,frame=on] \par
\externalfigure[more] \par
\externalfigure[more][width=4cm,frame=on] \par

\useexternalfigure[more][][test][background=color,backgroundcolor=red]

\externalfigure[more][width=4cm,frame=on] \par
\externalfigure[cow.pdf][less][frame=on] \par

\startpagefigure[cow]\stoppagefigure

\stoptext
