Tamron 28-75 focus shots - Is it bacjfocussing?

[thepacifist]

Hi all,

I am new here and unfortunately have to be impolite enough to ask for help from the experts here as my first post. So please bear with me.
I just got the Tamron 28-75 for my Canon 7D and headed out to the Botanical gardens to shoot. Fir the entire time, my Canon 7D was on "Full 19 point autoficus" mode

My pictures came out out of focus.

I used the back-foscussing chart to take images at 28mm, 50mm and 75mm respectively. I changed the autofocus mode to spot focus for these tests. Please let me know if the lens is back focussing? Does a 19 pt autofocus mode lead to more out of focus shots than a spot focus? I looked at the raw images in perture by overlaying the focus points on the image. The images were out of focus on the focus points.

75mm



50 mm



28mm





Any help would be greatly appreciated.