Currently on a Canon 40d i have a Tamron 18 - 250 1:3.5-6.3 LD DI Mark 11. I am not totally happy with the quality of the images but having said that at times the lens performs very well it just appears to lack consistancy especially when using it at the longer end of the scale. I need a lens starting around 17/18mm and prehaps a small zoom. I do not have a great budget but I am prepared to wait rather then buy a "cheap " lens. Any help would be appreciated or am i being unfair to my Tamron