Difficult, and everyone has different choices preferences. ( based on nikon lenses ).... had the
-60 mm with 2x TC. Benefits, AF still kinda worked, draw back, you had to get so close, the Jaw fish could almost kiss the port glass, and strobe positioning was difficult ( no space). Forget this set up with shy animals.
- Now for the 105 with 2xTC. Slightly more distance, like this set up the best. Forget about AF, and as such faster moving animals are hard to shoot ( then again, Nudi branches are not exactly Brare Hare ). You are probably limited to stationary subjects. Jaw Fish an Gobies still hard to get really close to, but I have some great shots with this set up of i.e. cronoid shrimps
- 200 mm with 2x TC. Again, every " Design " has its draw backs and benefits. Donthave this set up, but assume it would be good for shy animals. Draw back would be probably its long length of the lens, possible camera shake, and recon it will have the same auto focus problems as the 105 with the TC.