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Question: Thanks a ton for those who responded to my earlier query. what is the difference between tamron 17-50 vs Tamron AF 28-75mm? which is better of two?
Document: I just purchased this lens. I LOVE it! I wanted something that was a little wider than the 28-74 (or whatever that is) but still had the 2.8. I was a little worried about going with Tamron vs. Canon, but for the price difference it was worth a try. Its very sharp and the colors are great!
Feels fine to me.OK, after all that, I still returned it ONLY because I also ordered a Tamron 28-75 at the same time and I don't need both. It's probably a personal thing, but I like the range on the 28-75 better. If no 28-75 existed, I would keep the 17-50.
I have had the Tamron AF 17-50 f/2.8 lens for almost one year. It was first used on a 30D and produced wonderful photos. The lens seems nicely built and balanced well on the 30D. I updated to a 60D and, if anything, the photos are even better. I have used this during family picnics, during trips to the mountains and beaches with various degrees of light, indoor parties, and kid basketball in not-very-well lit gyms.
They didn't affect image quality but it still bothered me. So far I've found 1 tiny dust spec inside the lens, so this may or may not be a problem but I thought I would mention it since my last Tamron experienced this.A friend of mine got the Tamron 28-75 and I have to say that I like this lens a little better. As far as sharpness goes, both are great but the 17-50 has much better build quality.
Focus is quick and right on though a little noisy. Overall, a very good lens.RANKING: With all of the above in perspective how does it rank? Compared to Canon's 17-40L 4.0 I think the Tamron come on top. Here is a breakdown of the Tamron strenghts and weaknesses compared to the Canon 17-40L.Strengths1. Faster lens (2.8 vs 4.0). That can make the difference between taking the shot or missing in a low light situation.2.
Now perhaps I just becoming a better photographer, but the dramatic difference in the quality of the shots this trip vs. the previous one speaks for the differences between the lenses used.Negatives for this lens? From my point of view, nothing I can come up with yet.
So what is the criteria for a perfect kit replacement lens? It should have better IQ than the original, better build, have similar reach, faster and not weight a ton. The Tamron 17-50mm is all that. The lens is tack sharp, has excellent IQ, give F/2.8 across the entire zoom range, weights a mere 450g, and is well constructed.
Rotating focus ring: Sometimes I could feel it move under the edge of my finger tips but in practice my fingers fell behind the ring so again: no problem.The inclusion of the hood was very nice. Something like $40 extra for a hood for the already ~$1k Canon 17-55 IS? Thanks, Canon: that helped drive my choice of the Tammie. Saved a ton of money and got a great lens.
Optically, it is very similar in sharpness. it has some focal lengths which are slightly stronger, some are slightly weaker, but the difference is pretty much negligible from the tests I've seen and comparing it to my Tamron. Here are the advantages of each:Canon 17-55 F2.8:USM Autofocus with Full Time ManualImage StabilizationSlightly longer in the tele endTamron 17-50 F2.8:Half the price of the CanonSmaller and lighterSlightly wider 17mmThey are both excellent lenses.
I purchased a 60D Body (incredible) to replace my aging Rebel XTi. After a lot of research (20+ hrs of reading reviews), I finally narrowed my search for my for a new lens down to two Candidates, the Tamron 17-50 w/o VC and the Canon 18-135 IS. Why these two? Well after my extensive reading I realized that while I love taking pictures, I am not a professional photographer.
Answer: As far as I understand it, the Tamron AF 28-75 is a full frame lens.  Thus if you have a digital camera with a crop sensor (Canon Xti, T2i, T3i, T4i, 7D) it will actually magnify the lens to be 1.6x greater turning the lens into a 45-120mm.  This is not the wide to just over standard lens that most people want for an all around lens.  However, may be great for a portrait lens.  The 17-55 is a crop sensor lens and is thus equivlent to a 27-80mm lens on a 35mm camera which is the sweet spot for the all around lens.  If you have a full frame camera (35mm film, Canon 1D, 5D), then this 17-50 will not work on the camera.  It has smaller optics that will not drape light over a full size 35mm frame and will cause severe vignetting on those cameras.  Otherwise, I understand that optics are similar overall.  I admittedly returned my 17-50mm due to some pretty severe back focusing issues on two seperate copies of the lens.  From what I have read this may not be as much of an issue on the 28-75 and if I was willing to wait, I hear the Tamron customer service is pretty good about servicing these lenses.  However, I ultimately went with the Sigma 17-50 with the IS, and have been more than satisfied except for the additional $100 cost.