I have both this Tamron lens + my wife insisted on buying latest and greatest Canon EF 24-70mm f/2.8L II USM Lens. I tested both lenses and my not very professional conclusion is: 1) their sharpness is absolutely the same except 2.8 where Canon is a bit better 2) Tamron is lighter and more compact...

The Tamron 28-75 XR AF is one of my favorite lenses. It's hard to beat the quality, speed and price

Inexpensive; 2.8 aperature; quick focus; zoom lock; a good product overall

Body could be constructed tougher; could be sharper; sunshield is made of really weak plastic

I use it on my d800. You can get nice results with f2.8, although it does back focus or soft focus sometimes, especially if you shoot few frames in a row or in a low light conditions.

Yes, I would recommend this to a friend

Consistent Output; Durable; Easily Interchangeable; Lightweight; Quick Focus; Sharp Focus; Strong Construction

Difficult to Clean

I haven't had the lens very long, but it has been very nice for the money. I have used it in various situations and it has performed reasonably well. I am happy with my decision to purchase it.

Easily Interchangeable; Nice Bokeh; Strong Construction

Lens Creep

I haven't had the lens very long, but it has been very nice for the money. I have used it in various situations and it has performed reasonably well. I am happy with my decision to purchase it.

Easily Interchangeable; Nice Bokeh; Strong Construction

Lens Creep

Was torn between this or a prime lens in the 70mm range for portrait work. Chose this for the versatility of the zoom and the previous reviews that touted the sharpness of lens. It didn't disappoint. This is the sharpest lens in my arsenal.

Consistent Output; Razor Sharp; Rugged; Strong Construction; Versatile

Hunts in low light; Slow Focus

I expected better image quality from this lens. To say that I am disappointed would be an understatement. I own other Tamron lenses that far exceed the optical qualities of this lens.

This is a fast lense for sure. However, it has MAJOR focusing problems even under moderate lighting. I tried mounting it on my D5100 as well as my older D70s. Even the cheap kit lense does a marvelous job of focusing as compared to this one.

I bought actual canon lenses in other focal lengths now I am looking to replace this. There is no comparison. You do get some good images with this but not nearly as high quality. It has worked well for me for a few years. When you zoom in all the way does not focus well and extremely "soft" images.