a hands on review
After my last trip to Walden Pond, I began looking for a macro lens that was longer than the Nikon 60mm I had been using, yet still small and light enough to be tucked easily into my already too-full gadget bag. I have a Nikon 105mm macro which is a superb lens, but it was larger than I cared to lug around on the trips. Sigma makes a 70mm, but that was too close to the 60mm I already had to make a practical difference. I wanted something in the 90mm range, and found it in the Tamron 90mm Macro.
Tamron has two 90mm macro lenses -- a new one with vibration reduction and a fixed length when focusing, and an older model whose barrel extends when focused close. This is the one I settled on. It weighs only 14.29oz (405g) and is a short 3.8" (9.65cm) at infinity focus. This is only a tad larger than the Nikon 60mm I had been carrying with me. Perfect -- if it could perform.
The Tamron 90mm f.2.8 SP AF DI Macro lens set to infinity focus.
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| When focused as close as it can go, which is to say 1:1, then lens barrel extends out to 5.75" (14.6cm). |
Most macro lenses are built to perform with little or no distortion and the Tamron 90mm follows suit. It was sharp overall with a flat field, auto-focused quickly, and produced no noticeable vignetting.
Unlike its newer brother, this version extends the barrel as it focuses closer. At full extension its maximum aperture also drops from f/2.8 to f/5.6. A drop in aperture is normal for macro lenses as a result of the added extension. Lenses that do not extend are generally preferable, but for me the packing size was the most important consideration. The lack of VR also contributed to keeping the weight and heft of the lens body low.
This lens has an unusual feature for switching itself from manual to auto focus. Instead of a switch on the barrel, the entire focusing ring moves in and out to change modes. I was hesitant about this feature at first, thinking that it might be an easy way to move the lens from one focus mode to the other accidentally. After using it for a very short time, however, I found it to be far more convenient that the standard switch method found on most macros. For one thing, macro lenses often hunt excessively for focus due to their long focus range. The push-pull collar on the Tamron was a quick way to manually override and correct the focus and then switch it back again to auto once it was within range.
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| The lens is set to manual focus mode on the left with the focusing collar pulled back. A blue line around the front of the lens quickly identifies the mode. On the right the lens is switched into autofocus mode with the focus collar pushed out. The blue line also disappears. |
The lens comes with an accessory lens shade, but I found it to be unnecessary to put it on because the front element of the lens is so recessed it provided all the shading and protection I needed.
This series of lens is what Tamron terms DI. This stands for Digitally Integrated, and refers to the extra multi-coating of lens elements to make them perform better with digital sensors. It also has an internal motor for autofocus so it can work with camera bodies that do not have their own built-in focusing mechanisms.
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| Focus was quick and accurate for a series of bee photos I did. The bees were darting around quickly, and I also chose to work with the aperture fairly wide open so I could obtain a shallow depth of field. This made my dependance on the quick and accurate focusing ability of the lens all the more critical. |
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| This 1:1 shot was taken at full extension of the lens and aperture at f/5.6, which means wide open when this close. |
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| Lens bokeh is very pleasant as can be seen in the roundness in the background blurs. One of the reasons I wanted a longer focal length macro was to obtain shots like this with a softer background. |
Another benefit of having a 90mm macro is that it is also a perfect focal length for portraits, providing a very pleasing perspective in a head and shoulders shot.
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| This portrait was directly back lit with soft light from a window, and with the lens aperture wide open. Even in such difficult light, the Tamron provided good contrast and was able to autofocus quickly and accurately. |
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| This side by side illustration shows the long throw of the focusing barrel as the lens moves from infinity on the left to its closest 1:1 range on the right. |
Conclusion:
In terms of performance the Tamron 90mm SP DI Macro is a champ, performing equally well at all ranges from infinity down to 1:1. It is an ideal focal length for portraits and for close up focusing where shallow depth of field and greater lens distance is desired.
The build quality of the lens is light plastic so it does not have the toughness associated with most pro lenses. Nonetheless, this does keep the weight down, and for me that was a prime requisite. The long throw of the lens barrel is usually not desirable either, but serves the same purpose. In addition it also helps keep the cost down to around to a $500 range.
The VR version of the 90mm macro might be a better choice for serious work, but it is also more expensive, and heavier. For my purposes, the lens tested here does the job in a nice compact body.
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