Re: Tamron 180/3.5 Macro vs Nikkor 200/4 Micro
First-The Tamron is not better than the Sigma. I've shot hundreds of slides with each. They are both phenomenal lenses, and handling should be your determinant. If you want to use tc's then the Sigma (180 or 150) may be a better choice. Optically they are even and I spent a lot of time looking. Please don't take this as a knock on Tamron, I think it is a great lens. I've just seen a lot opinions that are not based upon hands on experience and one poor comparison on the web that is often referenced. These are contrary to what I've experienced and what so many other knowledgeable photographers have stated. Sorry...had to vent. Anyway...both great glass.
Second-I think that the Nikkor is worth the extra and I sold my Sigma after I used the Nikkor for a while. I'll try to break down why.
-The bokeh is phenomenal (best I've seen including the Tamron 90..which I like a lot)
-It has the best resolving power and edge-to-edge sharpness that I've seen
-Contrast is better than the other two (and they are VERY good)
-I think all of the above combine to give that special "glow" or "pop" to images taken with this lens
-Handling is a dream. That being said, I almost always manual focus macro shots and the MF throw and damping is perfect. I liked the Tamron, and thought the Sigma was even better, but the Nikkor is the best. If you use AF then the Sigma would be best followed by the Tamron...the Nikkor would be my last choice for AF.
-The tripod collar is perfect! Smooth, low profile, solid.
-Smaller, lighter, easy to hike with.
-Built! The AF/MF ring is a known weakness, but I never use it being in MF all of the time.
Ok, this is all from my actual experience. I am a field nature photographer, so that is my perspective. I don't shoot coins, watch faces, newsprint, brick walls, or anything of that ilk. I have no doubt that there are others who feel differently about things. If they have used all three lenses and have a different opinion, I completely respect that. The reality is that if I spread out a thousand slides and asked which slide came from which lens, only a very few individuals might be able to do it on a limited basis. I do think that the 200MicroAFD is one of those special lenses that I can actually do this with, and even then...not always. All great lenses...the gift of macro...no bad glass
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