Helo,i just upgraded my gear to a 5dmk III with a 24-105...i used to have a pentax k20d since 2008..I am a graphic designer and work mostly with posters, logos, catalogues, advertising, and ofcourse photographs i need for my work (product, scene, urban, portrait...) Im on a tight budget since i paid 3699 euros for my new canon kit.Im looking for a very sharp versatile lens that would give me the b