Hi all. Call me a supernoob but i have a question: where are the aperture/f-stops?? This is a SMC Pentax-FAJ 28-80mm F3.5-F5.6 -AL- Auto Focus Zoom lens that i'm looking at on eBay. I'm trying to get a wide angle lens for my Pentax k-1000. I've found a few 28mm lenses (those are primes right? lol), but I'd rather have something like 28-70mm, so that i don't have to change back and forth to another lens. Anyway, yea, i'm a noob -.- ..Any help appreciated!