I have put together a lens comparison test of the Canon 16 - 35 L II and the Tamron 17 - 35 2.8 - 4.0. I was in the market for quite a while looking for a lens which would satisfy this zoom range. I initially tried the Canon 17 - 40 L but I just was not happy with the sharpness nor the maximum aperture of 4.0. I finally bit the bullet and dished out the $1350 for the Canon 16 -35mm L II. It was suppose to be the best in its class and the price reflected this.
I noticed in my research that the Tamron 17 - 35mm 2.8 - 4.0 had gotten few but good reviews. I had the opportunity to buy and return the lens within 30 days so I decided to buy it and do a lens comparison between the two lenses to see whether the extra $1,000 was worth it.
For the tests here, I shot both at the aperture of 2.8. I did this because I knew that this is where I would mostly be shooting and also where the weakness of a lens usually is (wide open). I shot the flowers and the sign both at 35mm @ f/4. No post processing such as brightness, sharpness, exposure, saturation, etc... was done. The were both shot in RAW and then converted to Jpeg.
Here are the results. Click on following link to view more (as well as larger) images and my own conclusion.