When you take a lot of pictures of bugs, you need to get close to capture the detail. That means that a Macro or Micro lens is a necessity. At the moment, I have two. The 60mm f2.8D Micro-Nikkor, an older design lens and the newer 105mm f2.8 VR Micro-Nikkor.
Why Micro and not Macro? Well, taking pictures of very small subjects used to called Microphotography. In fact, that is still the definition of microphotography but, most folks use a microscope. Macrophotography used to be taking pictures of very large objects but, that was never used much. Nikon is a precision optical maker, they don’t just make cameras they also make microscopes. So Nikon stuck with Micro-Nikkor for their close focus camera lenses.
The reason you want more than one focal length is primarily to control the working distance when shooting. Both my lenses will produce a magnification ratio of 1:1 meaning that the image on the digital sensor is the same size as the subject. The difference is that you have to be closer to the subject with the 60mm than you do with the 105mm. Shooting live bugs in the open means that you can be a little further away and less likely to spook the critter. so, longer is better. Nikon makes a 200mm Micro-Nikkor but, at $1600, that’s a little heavy on the wallet.
At 1:1, the minimum focus distance from the specifications for the lenses is
60mm – 7.3 inches
105mm – 1 foot
200mm – 1.6 feet.
I happen to have the Nikon TC-14E and the TC-17E II. WHich provide additional magnification of 1.4X and 1.7X respectively. These are the newer models which don’t support the screwdriver of the 60mm f2.8D so, I can only use them on the 105mm. A lot is said about image degradation with TCs. Generally, the TC-14E is said to have little if any impact on image quality (IQ) and the TC-17E II only a slight amount. I try to get my subjects well focused but, I don’t necessarily want to get too close since I like to have some of the environment in the picture. I think it makes the picture more attractive and so long as I have enough detail to identify the subject, so, for my purposes the TCs work just fine. Here are a couple of examples.
Nikkor 105mm f2.8 VR
As far as I’m concerned, the loss of a little pixel-peeping detail doesn’t mean that the use of TCs should not be considered. Particularly since I shoot my bugs living free in the wild. If I were shooting them for scientific purposes and needed to observe very specific anatomical detail, I’d have the camera on a bellows and focussing rail in a lab shooting at a dead bug.