What are we doing wrong with this lens?

<p>The most prominent pattern of blurring in both images are centered at and rediates from the very center of themselves. This is indicative of change of FL or movement of the zoom ring while the shots were taken. There's also some general motion blur due to camera shake and subject motion. </p>

<p>I'd say its a crook lens. It's trying to focus in the center but not further. My guess is that an element is not moving correctly. You should see it stopped down. Go back to the shot with the camera and exchange it for a Sigma HSM or Tokina ATX pro. Of these three generic brands I'd put Tamron third in the quality stakes. For $700 you would not be far away from a genuine Nikon or Canon secondhand.</p>

<p>The focus effect looks very similar to that of a Lensbaby. I suggest you take the lens back and ask for a replacement as it definitely shouldn't behave the way it is.</p>

<p>*Just further to my post, I'd only take it back if the effect is not being caused by the operator turning the zoom/focus rings on accident/purpose during the capture of the image.</p>

<p>How do they look if you stop it down and try the same shots?</p>

<p>I'm not suggesting that it should be that lousy at f/2.8, of course. I am just wondering if it is worth a hang at any aperture.</p>

<p>--Lannie</p>

<blockquote>

<p>Camera shake defiitely seems to be playing a role here.</p>

</blockquote>

<p>Nope. If it were camera shake, the central part of the image would be that terrible, too.</p>

<p>--Lannie</p>

<p>When you stop it way down (which you obviously must), be sure that you are shooting aperture priority. (That will solve the problem of the dark image--unless there really is not enough light.)</p>

<p>Even so, the lens should do much better than this at f/2.8. It is flawed somehow. Yes, lenses do not typically perform as well wide open, nor do they typically perform as well around the edges as in the middle, but this is ridiculous.</p>

<p>--Lannie</p>

<blockquote>

<p>She is convinced that this is the way the lens is supposed to work and wants to sell it.</p>

</blockquote>

<p>Sell? Who would want to buy it? Return it to the store asap. If you didn't zoom during shooting it's a totally trashed copy. It happens and even "name brand" lenses can be out of whack sometimes, this is not a Tamron problem.<br>

Shooting at different apertures doesn't matter. Lenses can be a bit softer wide open but no lens in the world should look like this. (Lensbaby excluded.)</p>

<p>This lens have an push-pull clutch AF activation mechanism. The default position ( from the factory) for AF function is set to OFF. Just grab the focus ring and pull'it 2mm. Voila , the lens will work flawlessly.</p>

<p>Here are some examples I took as my canon 70-200 is usm as it was new. Shot at 2.8 some as slow as 1/100sec <a href="http://www.pbase.com/cwakefield/70_200">http://www.pbase.com/cwakefield/70_200</a> I am sure your Tamron lens is about the same. I would exspect the same sort of results.</p>

<p>Paul B., I admittedly do not know this lens, nor do I own any Tamron lens. Therefore, I concede that you could be correct, but what you say makes absolutely no sense to me. The center of the image is in focus.</p>

<p>Still, I guess it is worth a try before sending the lens back. . . .</p>

<p>--Lannie</p>

<p>So everyone agrees the lens is bad?<br>

Basically, it seems to do this when the Apereture is set bellow 3 or so.</p>

<p>It might look like some misaligned group inside the lens. Definitely, this IS NOT the way it's supposed to work.</p>

<blockquote>

<p>So everyone agrees the lens is bad?</p>

</blockquote>

<p>Apparently we are in agreement, although you might just try what Paul B. suggests above: move the focus ring a bit prior to shooting to see if that corrects the problem. I cannot believe that that is going to work, but I suppose that it is worth a try before you send it back. The idea that there might be some "push-pull clutch AF activation mechanism" (in the words of Paul B.) seems unlikely to me. Even if there is such a mechanism, it is hard to see how that would cause this particular kind of problem.</p>

<p>Still, I guess that it is worth a try before you send it back: before you shoot the picture, "just grab the focus ring and pull it 2mm.," as Paul B. says.</p>

<p>Why am I not optimistic that that is going to solve the problem? If you try it, in any case, push or pull it more than 2 mm.</p>

<p>--Lannie</p>

<p>I strongly suggest asking an experienced photographer in your town to go on a shoot with your wife. Let that person take some shots and then let your wife take some shots at exactly the same shooting variables (focal length, ISO, aperture, shutter speed). Then, upload both sets of images to a computer and review for sharpness. If both sets of images are unsharp, you have a defective lens--possibly because of one or more decentered elements.</p>

<p>The first image the camera is trying to focus on the rope cable in front of the fence.</p>

<p>The second image you need to set camera off the auto mode and use A mode or M, set the aperture to about f4, put the focus to continuous and if you do not have a fast shutter speed up the iso untill you get no less than 15000 sec, track the dog with your shutter button half pressed when the dog fills more of the frame press shutter all the way down and hold it there while tracking the dog, this will take quite a few shots but you can then choose the best afterwards.</p>

<p>It is not a lens fault.</p>

<p>Terry.</p>

<p>I have been looking for one of these lenses, I am willing to give it a shot if you do not want to send it back to Tamron</p>

<p>Here's one you can see the settings i used if you click on details tab at bottom of photo.</p>

<p><a href="../photo/9244458">http://www.photo.net/photo/9244458</a></p>

<p><img src="http://d6d2h4gfvy8t8.cloudfront.net/9244458-lg.jpg" alt="" width="600" height="827" /></p>

<p>Terry, can you dublicate that insane uneven radial blur by shaking your camera or misfocusing?</p>

<p>Btw: Exif indicates no auto mode was used.</p>

<p>Apparently we are in agreement, although you might just try what Paul B. suggests above: move the focus ring a bit prior to shooting to see if that corrects the problem. I cannot believe that that is going to work, but I suppose that it is worth a try before you send it back. The idea that there might be some "push-pull clutch AF activation mechanism" (in the words of Paul B.) seems unlikely to me. Even if there is such a mechanism, it is hard to see how that would cause this particular kind of problem.<br>

Still, I guess that it is worth a try before you send it back: before you shoot the picture, "just grab the focus ring and pull it 2mm.," as Paul B. says.<br>

Why am I not optimistic that that is going to solve the problem? If you try it, in any case, push or pull it more than 2 mm.<br>

--Lannie<br>

---</p>

<p>What he is talking about is that if you push/pull on the focus ring, it turns auto focus on and off.<br>

We know about that ring, she has autofocus turned on.</p>

<p>You can try that, but since the center is focused, I really don t see how this is a focusing problem.<br /> Unless she was playing with the zoom ring while shooting (as already mentioned), the lens must be a bad copy.<br /> I also don t see how it is an aperture issue... stopping it down might fix the image a bit, but it is supposed to work wide open as well. The images depict extreme distortion that resembles movement of some kind, not out of focus blur or normal quality reduction on the edges.<br /> In case you still have doubts about how the lens is supposed to perform, you can see proper samples taken with it using the link below, but my suggestion would be to go to the store right away... and you probably postponed that too much already...<br /> http://www.pbase.com/cameras/tamron/sp_af_70-200mm_f28_di_ld_if_macro</p>

<p>The top image looks like a Lensbaby photo, not the appropriate output. My guess is you have an element significantly out of alignment. No, <strong>it is not</strong> "how the lens is supposed to work"...</p>

<p>Ive seen this before on re-cleaned legacy glass where reassemble was done incorrectly and an element was reversed.</p>

<p>I think you need to send it back, there is something wrong with it. I checked the exif info and they should be sharp photos at those shutter speeds. You might make sure that you have it set to autofocus, other than that sometimes taking a photo of a dog running you should use continous focus setting to the AF will track the dog. Unless your shaking that camera pretty bad while shooting, it's hard to not get a sharp photo at 1/1000 shutter speed. I would get it replaced, if you bought it new they will replace it no problems.</p>

<p>Terry, can you dublicate that insane uneven radial blur by shaking your camera or misfocusing?<br>

Btw: Exif indicates no auto mode was used.</p>

<p>Kari i did not use auto mode i never do.</p>

<p>The first image looks as though the camera was trying to focus on the rope in front of the fence, also 1/1000 sec would not be fast enough if there was camera movement, if this was shot at 200mm (310mm on this camera) common practice states twice the focal lenth for minimum shutter speed (310mm = 620 sec min shutter speed for still subjects) but if the camera was not held steady you will get blur. If you look at the second image the dog is in near focus and the rest of the image is out of focus as should be at f2.8, if the shutter was faster and continous focus was used the dog would be much sharper but the rest of the image would still look the same (out of focus at f2.8)</p>

<p>I would try some more images with the camera set up right first, or let someone more experienced use the camera and lens before sending the lens back, i still think it is user error and not the lens.</p>