This is a full-frame shot of a mid-size fly. Details:
105 Sigma macro racked to minimum focus, coupled to 72mm of Kenko extension, coupled to a 1.4 converter, then body. (BTW, the placement of the TC matters; if placed immediately behind the lens, then the focal length changes to, in this instance, 147mm. However, if placed lens>tubes>TC, then the tubes have a greater effect, yeilding more magnification, but working distance gets smaller.)
The fly was gently chilled in the fridge in a Tupperware container for about 25 minutes. Everything was setup in the meantime. I got off nine shots before he flew away.
Light was provided by an sb-800 thru a Lumiquest lightbox at 12 o'clock, and a slaved old flash at half-power was fired thru a red gel. The slightly chilled fly sat on a piece of elevated glass for the shot. The glass allowed the red-gel flash to provide its light from the side and below.
Full-frame with this setup is about 8mm, yeilding a reproduction size of about 3x. Depth of field is kind of nano. But it was a fun, simple project.
Comments welcome,
Eric/Cerumen