  A technique is presented for producing synthetic images from numerical
simulations whereby the image resolution is adapted around prominent features.
In so doing, adaptive image ray-tracing (AIR) improves the efficiency of a
calculation by focusing computational effort where it is needed most. The
results of test calculations show that a factor of >~ 4 speed-up, and a
commensurate reduction in the number of pixels required in the final image, can
be achieved compared to an equivalent calculation with a fixed resolution
image.
