Double Lens Reverse Macro

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I wanted an MPE-65 a few years ago. This is a highly specialized macro lens that is pretty much a microscope attachment. It has a maximum working distance of a couple milimeters (?!) so it has no applications outside of macro settings, and the price-per-image is just not worth it at this time.  The good news is that up to 3:1 magnification can be achieved using a so-called double-lens reversing scheme.

The bad news is that clicking through websites to find this information resulted in a trojan and fake antivirus malware getting installed on my work computer, which I then spent several hours trying to remove.  Removal was successful, but in the process the computer became horrendously unstable.  This sub-story ends with a clean install of win7.

The implementation of the double-lens reverse setup is simple.  You buy a male-to-male filter ring, which is called a "macro lens coupling ring" on Adorama, and goes for $8.95.  Mount this on a longer lens, e.g. the 100/2.8 macro (max magnification = 1:1).  Then you screw on a shorter lens such that the rear of the lens is facing outward (see image above).  Magnification calculated as the ratio of the rear lens to the front lens (in this case, 50 mm mounted on 100 mm = 2x magnification).  With the close focus macro capabilities off the 100/2.8, the achievable magnification goes up to 3:1. 

The result is a setup that has high magnification, but has a very narrow dof, some distortion, and a working distance of like a centimeter.  I've tried ameliorating this with Zerene stacker, which in my hands works better than Combine ZM.  The advantage is that zerene generates an image with greater depth of field, but get confused easily if the images have distortion or are radically out of alignment.  The answer to this is a sliding ball head, which allows me to change the focal plane steadily, but even this isn't perfect (because the perspective changes substantially when the focal plane is advanced or retracted).

Anyway, some images that emerged from this effort are above.  I'm worried, though, about implementing this setup in the field, where wind and insect movement will shift subjects easily though the sub-millimeter dof.  ehh.