"Let me step away for a moment and address a question that I keep getting. One person expressed it like this: "when are you going to take Nikon to task for this being a variable aperture lens?"
I have news for you: all of the fixed focal length Micro-Nikkors aren't actually fixed focal length. In order to keep from being enormously long when focused at 1:1 magnification, Nikon (as well as many other macro makers) plays with the optical formula in order to keep from having an ever telescoping lens barrel. In macro work, you wouldn't want that, anyway, as a lens barrel that telescoped significantly to get to 1:1 would reduce working distance and potentially start hitting things in your scene at close working distances. Thus, at 1:1, this lens becomes about f/4.8 and does not extend even a millimeter. The aperture loss is actually a bit less dramatic at lower magnifications and the non-extension is very much welcome for macro use."
- Ian . . . [D7000, D7100; Nikon glass: 35 f1.8, 85 f1.8, 70-300 VR, 105 f2.8 VR, 12-24 f4; 16-85 VR, 300 f4D, 14E-II TC, SB-400, SB-700 . . . and still plenty of ignorance]
I own Nikon 200 F/4, 60 F/2.8 nano, & the 105 F/ 2.8 VR. They all shoot good. ... As for the Nikon-800E, with the 105. Mine won't open up at 2.8. Mine does the same. Stays at f/3.0
Recently my 200 f/4 does this, intermittently, also 800E. Won't open wider than 4.5 or 4.2. Some days 4.0 no problem. No rhyme nor reason. Indoors, outdoors. Good light, poor light. Warm, cold. Cannot discern pattern. Wondering if, like my own bones, the lens is just getting old.
I own the 105mm macro. If you are of a certain magnification or reproduction ratio, you won't be able to open up the aperture past a certain value. At 1:1 you end up starting at F5.6 or something like that.
I have the 105VR Macro. It is a wonderful lens. When you use it as MsMoto describes it has a good AF speed. Not as fast as other pro 2.8 lenses but plenty fast for most work. It is razor sharp on my D800.
If Nikon came out with a new one I don´t think I would bother looking at it - there is nothing wrong with the one we already have.
I have used mine as a walk around lens as I have been to cheep to buy the 85 :-) It works well for picking out people in a crowd.
As for the 2.8 thing I think mine does that when I get to close. I will have to check that out.
Oh yes, it is a fast focusing lens indeed! I actually feel a slight torque sensation when the lens focuses that I don't feel with my other lenses.
Everyones 105mm 2.8 can go to 2.8, but only as it focuses further away. Lens design and what not limit its ability to maintain that constant 2.8 aperture. Plus, at closest focus at 2.8 nothing would being in focus because the DOF would be so incredibly thin
Comments
"Let me step away for a moment and address a question that I keep getting. One person expressed it like this: "when are you going to take Nikon to task for this being a variable aperture lens?"
I have news for you: all of the fixed focal length Micro-Nikkors aren't actually fixed focal length. In order to keep from being enormously long when focused at 1:1 magnification, Nikon (as well as many other macro makers) plays with the optical formula in order to keep from having an ever telescoping lens barrel. In macro work, you wouldn't want that, anyway, as a lens barrel that telescoped significantly to get to 1:1 would reduce working distance and potentially start hitting things in your scene at close working distances. Thus, at 1:1, this lens becomes about f/4.8 and does not extend even a millimeter. The aperture loss is actually a bit less dramatic at lower magnifications and the non-extension is very much welcome for macro use."
"Discovery consists in seeing what everyone else has seen and thinking what nobody else has thought"--Albert Szent-Gyorgy