[jaieger]

Herro all,

I'm looking for a new lens to be my new walk-around lens, upgrading from the K-x kit one. I don't particularly want to get a lens that would complement/augment the kit lens (ie: the 55-300mm or tamron 70-300) cause the idea of changing lenses sends a shiver down my spine and freezes my face in a grimace of horror due to part laziness and part dust paranoia. So basically, I've been reading tons of reviews on various lenses, and I've come to the conclusion that I most likely want a superzoom..specifically, the Sigma 18-250mm and the Tamron iteration.

However, they seem pretty similar, so I'm in need of a little help in making a final decision...As I see it, these are the differences between them:

Sigma - less sharp but still very much acceptable (from what I've seen from tons of Flickr samples and read from reviews), faster/quieter/accurate-r autofocus, OS (the usage of which would conflict with pentax's built-in IS, so just use one or the other), better control over CA

Tamron - sharper, better IQ. but a bit harder to find due to being out of stock, and also maybe some potential problems with legit sellers, etc. ?

and as far as I can tell, that's the main difference, sharpness vs. autofocus, CA, handling..Do I have it right? Which one would you suggest for me? I mostly just go on walks wherever and take pictures of whatever I can find, so versatility is a huge bonus. I commonly find myself taking pictures of birds in flight or other animals and not getting close enough with the zoom, or scaring them off. Other than that, my photos range from macro to zooming in, which makes either of these lenses awesome for my purposes.

[rkt]

I used the Pentax 18-250 which is a Tamron re-badge ... and really liked it ... it is extremely convenient and probably the best walk-around lens if you can find one ... it has it's limitations specially when totally zoomed out ... but for non-serious shooting it seems to get the job done ... you should look at the MarketPlace section on this forum for potential sellers ... I can see one listed as of 10th July ...

[Marc Sabatella]

I would at least consider the possibility that you'll eventually get over your feelings about changing lenses (millions of people seem to have managed over the years). Not that superzooms aren't fine compromises, but it may turn out you've sunk $400 or more into a lens you grow out of rather into. Of course, you can always sell it if that happens, or keep it for more casual use.

[Ira]

My definition of a walkaround lens is a prime, focal length chosen for where you expect to be walking.

[jaieger]

I would at least consider the possibility that you'll eventually get over your feelings about changing lenses (millions of people seem to have managed over the years). Not that superzooms aren't fine compromises, but it may turn out you've sunk $400 or more into a lens you grow out of rather into. Of course, you can always sell it if that happens, or keep it for more casual use.

It's possible I spose, but probably unlikely. Several times in my photography class at school, we were given assignments to try out using different lenses. Even with the camera bag provided and only changing lenses sporadically, it was quite the annoyance as any excitement or emotion I had when I saw the shot I wanted to take just kinda went pffftt.. and puttered out in the time it took to change lenses.

My definition of a walkaround lens is a prime, focal length chosen for where you expect to be walking.

In a walkaround lens, I'm looking for sometthing that's versatile. Eg. taking a closeup of an insect of a flower, to a wide shot of a street, to zooming in on jittery animals.

[CWyatt]

the idea of changing lenses sends a shiver down my spine and freezes my face in a grimace of horror due to part laziness and part dust paranoia

Not that this relates too much to your original post, but I suggest you work on changing lenses if you want the most out of your DSLR. With some practice and the right set up, you can change lenses in most conditions in just a few seconds with little chance of dust issues.

Superzooms are certainly an alternative, but with a trade off in IQ, speed and sometimes size and AF speed.

In a walkaround lens, I'm looking for sometthing that's versatile. Eg. taking a closeup of an insect of a flower, to a wide shot of a street, to zooming in on jittery animals.

While superzooms are 'versatile', plenty of people on here will tell you a single prime is too, if you move your feet. Some people think that zooms, esp superzooms will make you lazy, not thinking about what you really want from the shot, or where you should take it from for maximum effect, or not trying something different etc etc. I agree somewhat, certainly depends on the user though.

[Marc Sabatella]

In a walkaround lens, I'm looking for sometthing that's versatile. Eg. taking a closeup of an insect of a flower, to a wide shot of a street, to zooming in on jittery animals.

The common mistake that many beginners make is to think only in terms of focal length when talking about flexibility. Yes, a superzoom has that type of flexibility. But with a maximum aperture of only f/4 to f/5.6 or so through most of its range, it lacks the flexibility of other lenses in that regard. And when it comes to closeups, there are far better lenses as well.

Again, not trying to talk you out of a superzoom for now. But I do suspect that soon enough you'll start to realize it too has limitations.

[jjdgti]

I agree with Mark and CWyatt:

The superzoom is a nice walk around lens and for those trips where yo do not want to take a lot of gear. Nice for outdoor shooting. However, for indoor or low light this one is not as good as a fast prime or a fast zoom for that matter.