I've been closely researching 200mm zooms (70-200's and similar), looking at the Tamron AF 70-200mm f/2.8 Di LD IF Macro Lens for my k-x. I like the professional and user reviews/comments about this lens. Although it's a bit of a "budget" lens, the optical quality, bokeh, contrast and sharpness are all generally highly praised by most (consumer and professional reviews). I've decided that it would be a better decision, above the sigma 70-200 (both models) for very good reasons (flare control, sharpness, purple fringing, etc.). Anyways the main thing keeping me from going ahead with the tamron is the fact that people say the autofocus is HORRIBLY slow. Well how slow is it? Each person has a different opinion of what slow is. If it's as fast as my DA 50-200MM WR, I'd be pretty satisfied. There are also MANY consumer issues with the aperture getting stuck with this lens. Anyways, these new lenses, seem to have decent optics, but more random defects than ever. I am really close to buying the pentax smc FA 200MM 2.8 IF as well. Since I almost always have my DA 50-200 close to, or at 200mm constantly (135-200+ just seems to fit my style). So, I want the tamron 70-200 di macro but paranoid about autofocus speed, I want the pentax fa 200mm 2.8 but it doesn't have the close focusing ability, and I really want the pentax fa 80-200 2.8 IF, but i'm not sure if that zoom would have much better optical quality/I.Q, than the newer tamron. Eh..........advice?
Last edited by outsider; 03-07-2011 at 03:05 PM.