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Tamron® SP AF17-50mm F/2.8 XR Di-II VC LD Aspherical (IF) Review Do you entertain yourself by reading lens reviews and spend hours on eBay looking for the ultimate lens? Do you have the desire to own every lens ever made? Does your camera bag weigh more than you do? Then you may be a good candidate to read this article.
It only costs about $650 USD, which is very reasonable for this level of lens quality and capability. A comparable Nikon-brand lens, such as the AF-S Nikkor 17-55mm F2.8 can cost over twice as much. Of course, the Nikkor lens has a stronger metal build and you pay for that. The Tamron lens barrel is made of “high-impact” polycarbonate so it can be lighter yet still maintain excellent strength for daily use. Let me tell you about my experiences with this lens. Not long after the newest version of the lens was released, I was given an opportunity by Nikonians.org and Tamron to use one for a few weeks. For most of December 2009, this lens was on my Nikon D300s. I used it as the “portrait” lens while shooting a wedding’s formal groups shots and as a “save my buns” lens when shooting the reception lit by white Christmas tree lights. Do you know how hard it is for a camera to focus on people dancing by candlelight. The Tamron’s wide F2.8 constant aperture was a big help. Tamron Vibration Compensation (VC) The Tamron vibration compensation—called VC—is simply amazing. Unlike Nikkor’s two-axis vibration reduction (VR), the Tamron has three-axis vibration compensation. How does VC work? Well, imagine the difference between a big plus sign “+” and a big “x” letter. The Nikkor VR system stops vibration in an up/down and left/right direction, like the plus sign. Tamron VC adds vibration compensation on diagonal movements, like an X.
When I’ve depended on VR while using my Nikkors—such as when a tripod is not feasible—I’ve always allowed a second to let the VR “take hold” before taking the picture. Otherwise background objects can have a weird repeating blur when the VR is not fully locked and the picture is taken. If you’ve used VR for any length of time, you may know what I mean. Things on the edges of the image can look really weird, like a failed Photoshop clone effect, even while the subject is sharp. I attribute this to the VR system not fully acquiring “lockdown,” in a sense, before the shutter is released. Using the Tamron’s VC system, I didn’t notice this effect at all. It seemed that the VC was faster at locking down the image. This is only my opinion, you may find differently. However, after using Nikkor VR from its earliest versions to the best VR II available today, I’ve grown accustomed to how it works. The Tamron seems to acquire the subject faster and locks down tighter. In my opinion, this VC feature alone makes the lens worth the cost. I handheld this lens in conditions that would make a less competent lens shudder—literally. Formal Portrait Work I used the Tamron during the formal portrait session in a wedding where I was limited to only two flash units, an SB-800 and a SB-900, with an SU-800 controller and Nikon CLS. By necessity everything was mostly direct flash. In FIG 2A, I used one SB-900 with its stock diffuser dome pointing somewhat toward the ceiling, on a Nikon D300s, and was working to control contrast as best I could.
I shot over 100 formal group portraits, with up to 21 people in them, during this wedding. Not a single image was incorrectly focused or badly exposed. Great lens performance. Low Light Performance During the reception of the wedding, all main lights were turned off, and everyone was dancing to strung-up white Christmas tree lights. The Tamron was able to acquire focus even under that very low light setting, with the assistance of the SB-900’s infrared beam, of course. I tried shooting these dark images with my AF-S Nikkor 16-85mm, but could not seem to get good autofocus. I quickly switched to the Tamron, with its constant F/2.8 aperture and that did the trick. However, the proof in the pudding is whether or not the full combination of camera, flash, and lens can provide accurate exposure under very difficult conditions.
FIG 3 shows an example of the type of image I was able to capture shooting basically in the dark. In the background of the image you can see the tiny lights that were used to provide a romantic atmosphere for the dancing. The bride and groom were dancing and spinning, while I was doing my best to capture them for posterity. The lens, once again, gave the camera and flash correct information for balanced exposure, with no blowout of whites or skin tones. The lens/camera/flash let the darks suffer, and kept the bride and groom exposed well. That’s awfully hard to do. Of course, in an image with this level of darkness, you expect to see some shadows go fully black, but the important bits were exposed correctly, and the image’s histogram just touched the highlight side of the histogram window. Under these conditions, that’s quite admirable performance from the combination. The Tamron can be trusted to deliver. Now, let’s look at some technical information for this fine lens.Technical Information (for Model B005) The Tamron® SP AF17-50mm F/2.8 XR Di-II VC LD Aspherical (IF) lens is designed for use on a Nikon having a DX imaging sensor. It does not provide a large enough image circle to cover the size of an FX sensor, so it won’t work on a D700 or D3s/x. It’ll work fine on all DX models from the Nikon D40 to D300s. Here is an acronym list explaining what all the symbols applying to this lens mean: Acronyms for Tamron® SP AF17-50mm F/2.8 XR Di-II VC LD Aspherical (IF) (Model B005)
As mentioned in the acronym list, the newest version of this lens (model B005) has a built-in autofocus motor (BIM), so it will work on the smaller Nikon bodies like the D40, D60, D3000, or D5000. Lens Sharpness I read a review at PopPhoto.com about this lens, and they were rating it as having comparable sharpness from F/2.8 to F/11. I had a hard time believing this until I shot the images in FIG 4. I cut these sample segments out from an area between the middle and edge of the images.
I can honestly state that the lens performs nearly as well wide open as at any aperture down to F/11. The reason I say nearly, is that I note some mild edge softness and slight light falloff in the corners at F/2.8. It’s gone by F/4. That’s to be expected in most all lenses. The absolute best sharpness is found at F/8 to F/11, but is entirely usable across all apertures. If you look closely at FIG 4, you’ll see a lessening in sharpness at F/16 as diffraction starts to take its toll. However, I would feel comfortable using this lens at any aperture. This is a sharp one, for sure! Lens Distortion To test for distortion I shot against a concrete brick wall at various apertures. I tried to walk closer or farther away to keep the blocks somewhat close to the same size, so that they’re easier to compare.
I note some barrel distortion at 17mm, but by 24mm it seems to be gone. Since the focal range on this lens is so short, it is easier to control for distortion. I really can’t see any distortion between 24mm and 50mm. Lens Flare What’s the worst case scenario for a lens? To be pointed directly into the sun. I gave this lens the acid test by standing in the superstore parking lot and including the sun in the image (see FIG 6).
As expected you can see the teardrop shaped rainbow effect chromatic flare in the lower right corner. In fact, if you look closely the greenish flare extends all the way from the left bottom corner to the sun. However, I’ve seen few lenses that don’t give you this effect, and it’s even added in movies sometimes since we are all so used to seeing it. The nice thing about this lens is that it maintained high contrast in the rest of the image. There is no milky effect that lowers the contrast of the entire image. The only areas affected by the sun are the actual flare reflections. The rest of the image is still high contrast and sharp. I would consider this good reflection control and shows that the lens has good quality coatings on its elements. Otherwise, an image with the sun in it would be very low contrast as the light bounces around between the elements. Light Falloff I was impressed with this lens’ minimal light falloff. I use a Nikkor 16-85mm and battle relatively worse light falloff. There is some light falloff at maximum aperture and shortest focal length (see FIG 7).
F/2.8 shows falloff it in the corners, but it is mostly gone by F/4. The only time I could really detect light falloff was at 17mm and F/2.8 and F/4. At any other focal length besides 17mm I could not detect any significant light falloff. There was just a tiny bit at 24mm and F/2.8. What you see in FIG 7 is “worst case scenario” in my opinion. This lens does not have serious light falloff problems, and what it does have is easily corrected in software. Chromatic Aberration To test for Chromatic Aberration (CA) with the Nikon D300s is a little more difficult than with some cameras. The D300s automatically removes CA when creating a JPEG. So, I shot this backlit tree on the left in FIG 8 in RAW instead, and processed it through Nikon Capture NX2 with “Lateral Chromatic Aberration” correction turned off.
The results were what I would call excellent. In FIG 8 you can see the red opaque area of the big image represented at 100% on the right. Even at 500% I could not detect significant amounts of CA. This is a worst case scenario, too. Backlit tree limbs will show CA when it is present, in my experience. Can you see any? I can’t! Sample Images from Tamron Now let’s look at three larger sample images. One of them I took in Knoxville Tennessee at the colorful front of a bankrupt Circuit City store. The other two were provided by Tamron, since I did not have the lens during a colorful season (December) and couldn’t get any beauty-in-nature shots. The two nature shots were taken by Tamron technical representative Rob Moody personally. He was using his Nikon D700 in DX mode (5.5mp).
Some Basic Lens Facts
A Look at this Lens Here are a few images of the lens from different angles. This is one good looking lens; don’t you agree? It takes pictures even better than it looks!
My Conclusions I would feel confident using this lens in almost any situation. It feels strong and robust, with a design and warranty showing that it’s made for many years of usage. While not up to the heavy standard of a metal Nikkor lens, it doesn’t cost nearly as much either. For a photographer that needs a good solid high-performance lens, but has to maintain a budget, this lens performs extremely well. I love the constant F/2.8 maximum aperture. This lets me use the lens to isolate my subjects with shallow depth of field when wide open, and have plenty of depth when stopped down. It’s surprisingly sharp wide open. The specs I’ve read on other more technical reviews show very similar sharpness results from F/2.8 to F/11, and some minor sharpness loss due to defraction between F/16 and F/32. Quite an impressive lens! It’s highly corrected and acceptable wide open, which is unusual in a lens of this price range. I read a review of an earlier version of this lens on Popular Photography’s website, and they claimed that it optically outperforms the Nikkor 17-55mm F/2.8 lens. I can tell you that the images I shot with it are very sharp and have excellent color contrast. It is a great normal lens for general use on a camera like the Nikon D5000, D90, or D300s. With the Tamron 17-50mm F/2.8 VC, other photographers will wonder how you took such sharp images. Pro quality images at a reasonable lens price! Keep on capturing time … Darrell YoungThank you for visiting PlanetNikon.com!
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FIG 1B - Tamron® SP AF17-50mm F/2.8 VC Lens
