Woohoo! I'm back in business, so here is the first of the posts I've been trying to send all day...
I notice a few people posting that they are looking for a constant aperture auto focus zoom available in a Pentax mount, that is around the 28-70mm (or 28-80, 28-75, 24-70, 24-90, 28-105 etc) mark. So, I was wondering - aside from the Pentax FA 28-70 f2.8, which lens is generally thought of as the "best" in or around this range? So, I am referring only to the "latest" AUTO FOCUS models available, as I know that there have been many variations over the years. Or if you have a particular favourite of a certain model that exceeds what is currently on the market, please feel free to name that one too. (eg, Tokina ATX Pro II etc). The Tokina 28-70 f2.8? The Sigma 24-70 f2.8 or ? The Tamron 28-75mm f2.8 macro? And, I just discovered that Sigma has two lenses available - they are 28-70 f2.8-4, and a 28-105 f2.8-4. They are only USD$119 and $199 respectively at B&H. Anyone have any experience with these? I particularly like the 28-105mm focal length (I have the Pentax 28-105mm FA Powerzoom, and I love it, but at f4-f5.6, it is just too slow), and the Sigma 28-105 f2.8-4 would certainly address the issue of speed that I have with the Pentax FA 28-105, but with these two Sigma lenses being so inexpensive, it makes me wonder why it is the case... Also, how many of the above have macro capabilities? And why is your particular choice your favourite? Bokeh? Sharpness? Flare (or lack of it)? Build quality? AF Speed? Price? Value for money? etc... Also, is f2.8 the fastest anyone has ever seen in a zoom lens of constant aperture? Is there any record of anything faster ever being produced? So, here is my "wish list" for such a lens - a sharp, nice bokeh'd AUTO FOCUS lens, focal length of 28-105mm, f2.8 constant aperture, less than usd$400. I'm not asking for much, am I?!? lol. Then, after this one peters out, I'll post another similar topic covering the f2.8, 80-200-ish zooms. I don't own any of the above lenses, so I can't really participate here, but I am leaning towards possibly purchasing the Tamron (when I can afford it!)... tan.
