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  Reviews by: jm_mac  

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Tamron 28-75mm f2.8 XR Di Zoom AF

Review Date: Aug 27, 2005 Recommend? | Price paid: $340.00

Pros: Build, optical sharpness
Massive front focus wide open/wide angle.

I bought this lens due to all the great reviews on dpreview. I bought it mainly for low-light, group, indoor venues at distance greater than 15 feet (i.e. from a close specatator's distance). Therefore, I planned to use it wide open at all focal lengths.

After taking plenty of pictures with it, I noticed that I had a high percentage of missed shots - my subject was very blurry. So I did what I never did before - I tested the lens. I found that wide open, wide angle, at over 10-15 feet, this lens couldn't autofocus worth a d*mn. However, I knew it was optically excellent because the few correctly focused shots were great, and I could use the parfocal technique to get correct focus, then zoom out.

I compared it against my other 5 lenses (all canons), and none had a focus problem, except for the 50/1.8 (only wide open). So I sent it back for the infamous "calibration." I got it back, and to make a long story short, the problem was still here. In fact, I did even more exhaustive testing than before and I discovered this lens has focus problems wide open, wide angle at *all* subject distances. When closed down to about f5.6 the depth of field increases enough to make the subject always in focus. But I paid for an f2.8 lens, not an f5.6 lens.

I plan to keep the lens. But for all intents and purposes, I will use it as a 45mm-75mm f2.8 lens, because below 45mm wide open, the focus is just plain UNRELIABLE.

Tamron 28-75mm f2.8 XR Di Zoom AF

Review Date: Aug 26, 2005 Recommend? yes | Price paid: Not Indicated | Rating: 2 

Pros: Built well, super sharp optics
Can't auto focus worth a d*mn when wide open.

This is the last of 6 lenses I own, the first 5 being all Canons. I expected a lot out of it due to all the positive reviews. What I found was very disappointing.

Between f2.8 and f5.6, at distances over ~10-15 feet, this lens cannot autofocus!!! Wide open, for example, if I focus on something 20 feet away and get focus lock, things about 10 feet away end up being in focus and my subject is very blurry. When I stop down to about f5.6 it gets much better - I suspect, however, that this may be due more to the depth of field rather than focus accuracy.

I know the optics are sharp because with close-up items, the pictures are gorgeously sharp. Also, even when wide open at distances greater than 10-15 feet, I get the occasional (maybe 1 in 10 or 15) picture that is focused well and is very sharp.

Overall, I bought this lens for indoor, low-light events with subject distances greater than 15 feet - exactly the situations where it has the most problems. I cannot trust it at all, hence the low score I am giving it.

Thankfully, I still have a bunch of Canon lenses I can trust. A couple may not be as optically sharp as this Tamron, but at least they focus faster and accurately.