Nikon Lens 105 mm 2.8 - OK on DX body?

[Suzan J]

Hello all:

I am seriously considering the purchase of this lens, the AF-S VR Nikkor 105 mm 2.8G IF-GD, to use for my "bugs and flowers". I realize it is quite expensive. I currently own a D3100 and I do not intend to upgrade any time soon. This was my first DSLR and I am still learning. I do take a lot flower shots and have been using my inexpensive Nikkor 50 mm 1.8 lens, which has no autofocus motor and forced me to learn manual focusing. I was pleased with some of my flower shots with this lens, but I would now like to branch out (no pun intended) and attempt to use a real macro lens.

My question really stems (again, no pun) as to whether this lens is overkill for my camera body. I am of the understanding that this lens is fully compatible with both FX and DX bodies, so if I do ever decided to purchase a D600, then I suppose it would be a better investment?? How do lenses manage to fit both bodies anyway? Are the connections the same size?

I understand that using specifically designed DX lenses on an FX body will work, but will result in loss of image size and severe vignetting, but what about the other way around?

Any thoughts would be appreciated.

[Clactonian]

This is an excellent lens and should serve you well for many years to come. I have successfully used this and similar lenses on my old D70 which is far less sophisticated than your D3100.
The mount is similar on both DX and FX cameras, but on the former only the centre part of the image is used by the smaller sensor.
Don't forget that because of the smaller sensor the image will be equivalent to a 150mm lens on a full frame camera.
You can find a review of this lens on a DX camera HERE

[DeepWater]

Ok Suzan - I am not an "expert" but necessity is the mother of learning, so here goes. First to address the FX - DX issue you raised. This all has to do with the camera sensor size. A FX camera (such as the D-600, 800, D-3, D-4, etc) has what is called a 'full format' sensor. It is roughly the equivalent of what you would get with a 35mm film camera. In order to make cameras more affordable all manufactures came out with what is called a cropped sensor, which is what you have in your camera. This sensor is smaller - for Nikon the reduction factor is 1.5. With regard to lenses Nikon has built a series of lenses that are made specifically for the smaller sensor - they will say DX (Nikon DX 18-55, etc.) on them. When you have a DX lens on a camera that has a cropped sensor (like yours) your field of view through that lens will be exactly what it says - an 18mm DX lens will get you a field of view (how much from side to side you can see through the lens) that is aprox 100 degrees. Now, take an 18mm lens that is built for a FX format camera and put it on a DX camera and your field of view will be reduced. You may have heard that a FX lens on a DX camera will give you a "longer" lens - not really true, it just looks that way because of your field of view is reduced.
If you want to know how this will work in practical terms here is what you do. You are looking at a 105 mm lens - it is a FX lens going on a DX body. The crop factor of your sensor is 1.5 (this is Nikon's ratio) - so what you do is multiply your lens length (105) by 1.5 and your will get your field of view. So your 105 mm lens will be the equivalent of a 157.5 lens - your field of view will go from 23 degrees to somewhere around 18 degrees - simply put if you put this lens on a d600 it would be a 105 mm lens - on your camera it will appear to be a 157 mm lens. Is that clear as mud?

All Nikor lenses will fit every Nikon made (Not of course point and shoot type cameras) - because the mounts on all cameras are made the same (not exactly true but close enough).
As to the lens itself and will it be a good investment? All Nikor lenses are good quality products - some are better than others, and I suppose Nikon has made some stinkers, but I have heard good things about this lens. I don't have it so can't give you and practical words based on actual shooting but as long as you understand the issue of crop factors and field of view and know what you are getting you can't go wrong.
I am going to be buying some new glass in the future (soon I hope) and I too shoot a DX camera (d-300) but I am intentionally going to buy lenses formatted for a FX camera because I intend to upgrade to a FX body one of these days - if you have DX glass and upgrade to a FX body all your glass is useless.
A practical example of "field of view is this: lift your eyes from this screen and look straight forward - now, without turnning your head, look side to side. The entirety of what you can see is your field of view. Now take your hands and put them up next to your eyes, palms facing forward - slowly turn them in so that your palms are facing each other. As you do this you will notice you can see less and less as your field of view constricts. This is exactly what is happening in a lens. A "longer" lens gives you a narrower field of view - and the converse is also true. This is something you need to understand when choosing an lens so that you know what you are going to get.
Hope that helps. I am going to try to attach a PDF for you that you should find helpful - don't know if it will work but am going to give it a shot.

[Manfred M]

I've had that lens on loan from a friend for a few months and have played with it over the past couple of weeks. Its owner shots a D300 (DX sensor) camera.

I've tried it on my D90 (DX sensor) and my D800 (FX sensor). The lens is good and sharp. I found it long on my D800 and insanely long (focal length) on my D90. The advantage of being long is that I was able to light my subject quite nicely without casting any shadows. The disadvantage is that I have to shoot from a long way away, which means I have to have sufficient clearance between the lens and subject. Because of the long focal length, I found myself prefering the full-frame camera, rather than my crop frame. I could probably live with it on the D800, but would probably go with a shorter lens on the D90, if I were to buy one.

If you are shooting macro, assume you are going to be focusing manually. None of the macro shooters I know ever shoot any other way, so you are going to have the same "issue" that you have with your manual focusing on your 50mm lens. I would have to agree, the depth of field is so narrow, manual is the only way to go. I find that I did you Live View" for the shots and maginified the display for focus assistance. Don't forget to cover your viewfinder if you shoot this way. Trying to shoot with autofocus was an exercise in futility that I gave up on quite quickly; the camera could not find and keep the focus point I wanted.

In the end, I gave up on the 105 and switched to my f/2.8 24-70mm lens. I was shooting Christmas tree ornaments for a new intro on my Facebook intro page, so the shots were not "true" macro shots.

[evan47]

its a great macro lens, get it. the earlier af-d version is smaller and lighter. probably stops down a little better too, but has no motor or vr. at minimum distance the image is the same size on dx or fx.
at more normal distances the lens will give about 150mm focal lenght on dx.

[Suzan J]

Thank you for the responses to my question. I will put this lens on the top of my wish list. I have the same plan as "Deepwater" which is to invest in better qualify lenses that I can eventually use on my future full frame camera. Lord knows when that will be, but my current camera will keep me busy for some time yet.

[Letrow]

Suzan, just a few remarks from my side. I use this lens on a D7000 (DX), which works fine. For you it should work as well because it is a newer Nikkor lens. The only problem you might have with your body is that older lenses (e.g. D lenses) would not focus. This is because they are driven mechanically by the camera body (higher end models can do it, but yours can't). The new lenses have an internal motor, so they can work with lower end bodies.

The autofocus is great on this lens and although the VR won't help much at macro distances, it seems to have a slight positive influence, which helps handheld shots.
I don't fully agree with Manfred, although he has a valid point when he says that most macro shots need manual focus. With AF-S enabled on your camera though you can do a lot of macro shots while using autofocus.

Great lens, also in view of later upgrades.