You probably think of the AF 200mm f/3.5 ED, the bigger brother to the AF 80.
They are both good lenses, but hampered by the imprecise manual focusing due to the play of the focusing collar. Neither lens is suited for fast action photography because of this issue.
Unfortunately, although both are "chipped" their CPUs are incompatible with all Nikons other than the F3AF. I swapped out the factory chip for my own to get full metering ability restored.
As to the "front" objective, microscope optics can be tricky to use as they frequently are dependent on the ocular to correct various aberrations, and often are designated for viewing rather than photography. The Mitutoyo objectives (made for metallurgy I believe) are infinity corrected, APO, and provide a quite long working distance given their magnification. You can get them from 1X to 50X, 5X and 10X probably being the most frequently seen. As infinity optics they need a lens of 200mm focal length to form the final image. You can use various approaches to this end, from standard 200mm lenses to Micro-Nikkors, or even highly corrected close-up attachments (Raynox etc.). I have the 5X, 10X, and 20X, Mitutoyos.