While test various styles of diffusers I came across a one involving a rather unique method of removing highlights: cross polarization. As detailed in Wil Hershberger’s article here, this technique involving a polarizing filter and special polarizing film to cover the flash(s). I constructed a similar setup to the one shown in Wil’s article but with the Canon 100mm macro lens and MT-24 EX macro twin lite.
On the whole, the results of these tests were fairly pleasing – little to no highlights and pretty good color. But this did not hold for insects with iridescent coloration; the images of these species were dull and lacking in much of the natural coloration. Below is a combined series of the better images:
In all I found this method reasonable for only certain insects – ones with much iridescent coloration (particularly tiger beetles) were not well represented by this method.