Originally posted by bolek What single lens can do it all?
NO such lens. If there were such a lens, the K10D would be sold with it -- and the cost of a K10D would be around $5000.
Question almost doesn't make sense. Remember, one of the main advantages of DSLRs is their ability to use interchangeable lenses. If having a single, very capable lens is central to your happiness with a camera, send the K10D back and get a high-end fixed-lens camera like the Lumix DMC-FZ18 or the Canon G9 or SX100 IS. These cameras have excellent lenses aimed at a very broad middle range of uses, and they can take outstanding photographs.
That said, the Tamron 18-250 is a wonderfully versatile lens and has pretty good image quality. But whether it's a good lens for you, depends on what you're shooting. I got the 18-200 fairly early on, when I was still trying to get my dslr to work like my old Canon PowerShot S3. I recently sold my Tamron 18-250 because, excellent though it is, I just wasn't using it. For many amateur photographers, the 18-250 will be a great lens. But if you are really using your dslr to its best advantage, then you're going to move more and more to special lenses for special uses. If you're shooting indoor sports, the 18-250 is not fast enough. If you're shooting birds, the lens is not quite long enough. If you're doing street photography and trying to be inconspicuous, this lens is too long. If you're doing macro or portrait photography, well, this might not be the best choice for either of those tasks, either. For product or fashion photography, the image quality is not tops. And so on.
Quote: I just got K10D and 18-55-F3.5-5.6 AL. Is it good lens?
What's "good" mean here? Is it reasonably sharp? Yes. In that sense, it's good. Not great, but it's good. I'd prefer to say "fine", but it sounds like fine will be good for you. Generally reviewers seem to think that the Pentax kit lens is one of the better kit lenses available. I gather that the kit lenses from Nikon and Canon are not very good.
That said, I sold my kit lens shortly after buying my first additional lens. When I bought my next two cameras, I bought bodies only. I now have a Sigma 18-50 f/2.8 that I think is a good bit better than the kit lens -- but it cost a lot more, too.
Quote: Which lens will be the best to:
1) take picture at high school basketball game – motion – not the best lighting in the Gym?
There have been a lot of threads here on that subject, many of them started by me. Basic answer is that you need a fast lens to shoot indoor sports. Maybe NBA auditoriums are so well lighted (for television) that you could live with f/3.5, but in the school gyms that I shoot in, f/2.8 seems a minimum, and I get better exposed shots with my 50mm f/1.4. Of course the problem with the 50mm prime is that it's not a zoom. So I go back and forth.
What zoom range you need depends entirely on where you're going to be able to stand. I have been shooting elementary school volleyball and basketball, and elementary through high school swimming. I am generally able to stand right at the edge of the action. Last volleyball game I shot I used my Sigma 18-50 f/2.8 and it works fine, although I cropped the shots more than usually. I would have used my Tamron 28-75 f/2.8 if I still had it. Sometimes I use the 50 f/1.4 and live without the zoom. Shooting a swim meet indoors last weekend I used the Pentax 50-135 f/2.8, but the pool was large and 135mm isn't really ideal for reaching to the other side of the pool. Earlier in the summer, at a meet outdoors, I was able to use my Tamron 18-250 and get good results -- in great light.
You asked also about exposures. If you're shooting basketball or volleyball indoors, you're going to want a reasonably fast shutter speed. I do sometimes go below 1/320th sec but I'd prefer not to, and when the lighting's good enough to go to 1/500th sec I'm much happier. However, in the school gyms in my experience, setting the shutter to 1/320th sec and opening the aperture wide open (f/2.8) means I have to set the ISO fairly high -- quite often 1100 or higher. One of the nice features of the K10D is TAv mode. Check it out.
Quote: 2) Good weather – sunny – outside views or distance shooting – some zoom needed.
No one answer here. See above. What are you shooting outdoors? Distant wildlife? Get a 500mm lens or at least a 300mm lens. Flowers up close? Get a macro lens. Your family picnic? The kit lens will work fine there, probably.
Quote: 3) What 18-55-F3.5-5.6 AL is the best for?
It's a "normal" shooting lens, for people in good light, at fairly close range -- the kind of photos that the average amateur wants to take.
Welcome to the world of the (d)SLR. Hope this helps.
Will