Macro / Portrait lenses - Tamron/Sigma/Nikon

Hello,

<br><br>I need to buy a macro lens that also allows portrait shots -

I was looking at the Nikon 105/2.8, Sigma 105/2.8 and the Tamron

90/2.8.

<br><br>There are reviews about all of the three, in this site - I

could not find subject matter directly comparing the lenses with one

another.

<br><br>I also spoke to the sales guys at Tamron and they confess

that for anything closer than 15 feet, the lens cannot maintain F/2.8

and, in fact, the lens steps down to 5.6 for Macro shots.

<br><br>I haven't heard similar stories about Nikon or Sigma - having

said that, the Nikon is obviously the most expensive of the lot and

the Tamron lens offers defocus control for a lot lower price than the

Nikon....

<br><br>I use an N80 and a Nikon FE.

<br><br>Any opinions / suggestions?

<br><br>Thanks in advance,

<br><br>Naveen

None of those lenses will maintain a constant 2.8 aperture. It's called the bellows effect, and it's just something that happens -- at 1:1, you lose two stops. The only lens I can think of that doesn't do this is the old compensating version of the 55mm 3.5 nikkor.

About f/2.8 vs f/5.6: all real fixed-focal lenses do that (some "non real" lenses change focal length as you focus). Large format photographers call it the "bellows factor".

 

Essentially to bring a 105/2.8 to focus to 1:1 is has to be moved 105mm away from the film plane, so that you end up with the lens being "optically" 210mm from the film plane. The diaphragm is still 37.5mm in diameter, but it is now "optically" 210mm from the film plane, which is why the "effective" aperture is f/5.6.

 

Confused? Yes, it is confusing.

>The only lens I can think of that doesn't do this is the old compensating version of the 55mm 3.5 nikkor.

The Nikon 70-180 also doesn't change f stop. It close focuses by diopter effect, reducing the focal length of the lens. This was done to keep it from becoming vari-focal, but has the interesting, if unfortunate, effect of giving it the shortest working distance, I've read, of any Nikon micro lens at 1:1 at 180mm (you have to use a diopter to get to that magnification which reduces WD further).

 

So, yes, Mr. Naveen N, all all the lenses you discribe will have an f stop of about 5 or so at maximum magnification.

 

To answer your question, all the lenses you describe are probably quite good. Manufactures, even seemingly dreaded ones, don't seem to make bad macro lenses. Some people even like the Vivitar 100mm macro which costs about $100+. It seems to get recommended a lot, although I've never used it and don't really want to.

 

Now I have used the Nikon 105 2.8 micro and it's my favorite, most used lens (90+% percent of shoots or so). It's gloriously sharp, but costs $600+. It won't disapoint, and will hold its value well, particulrly if you buy a new lens used and take care of it.

 

However, and again, I haven't used it to a significant degree, the Tamron 90 2.8 enjoys a cult classic reputation. Many say the bokeh, or out of focus highlights, are better with this lens. Others have said it's not as sharp. I don't know, but the differences either way aren't probably that significant. The price difference probably is, although it probably won't hold its value well.

 

Other comparisons involve focal length. What kind of macro do you shoot? The Nikon's extra 15mm could, though probably won't, mean it wouldn't scare off an insect that the Tamron would. You could take the same picture with the Nikon from slightly further away.

 

Also think about your portraits. 90mm is better for head and sholder shots, the 105mm for tightly cropped heads, at least what I've heard, that's why portrait lenses come in 85mm and 105mm (and 135mm...) You could take either shot with either lens, though. Also the 105mm will flatten facal features and isolate macro pictures ever so slightly more, but its not the difference of a 300mm and 24mm by any means.

 

Do a search and you'll find some comparisons between these lenses, and maybe with the Sigma about which I know nothing.

 

But I think the only real answer is to test these lenses yourself. Bring someone you'd like to take a portrait of and a macro subject to the photo store and shoot a test roll and report back to us.

 

Contact me with more questions.

 

Matthew

<P> <i> I could not find subject matter directly comparing the lenses with one another. </i> </P>

<P> All I could find is the <a href="http://www.orchideen-kartierung.de/Macro100E.html">Tamron vs. the Sigma</a> and the Tamron is clearly better. Alas, no Nikon here.... </P>

 

<P> Happy shooting , <br>

Yakim. </P>

Thanks for the great responses everyone!

<br><br>Jean, your explanation rings a bell, I'll have to go back to high school physics for my clarification.

<br><br>Matt, I think I'll go with the Tamron, basically because of the 'hole-in-my-wallet' factor.

<br><br>Once again, thanks again for all the responses.

<br><br>Naveen