[wedge]

I'm looking for a single lens to handle the 18-200 mm (or more) range. Basically, I want something for traveling to avoid having to haul around multiple lenses. I've narrowed the choices down to these:

Tamron 18-200mm f/3.5-6.3 XR DI-II LD Aspherical (IF) AF Zoom Lens with Macro (~$230, after rebate)

Sigma 18mm - 200mm f/3.5-6.3 DC Autofocus Aspherical Zoom Lens (~$300)

Tamron 18-250mm f/3.5-f/6.3 XR DI-II LD Aspherical (IF) AF Zoom Lens with Macro (~$470)

I've had good luck with Sigma lenses in the past, but never owned a Tamron, though I've heard a lot of good things about them. I'm sure there are more differences between these two Tamrons than just 50 mm of focal length, I just don't know what. And whatever the difference is, is it worth twice the price?

Any opinions on any of these would be greatly appreciated.

[wjt]

I only have the Tamron 18-250mm so i can't compare it to the others, but its nice enough for what i want, and the wife likes to use my camera when its on. I know nothing about the 18-200's you mentioned so anything i said about them would be mostly speculation. I'll take a couple of snaps today with my tamron and post them if you would like.

[Jodokast96]

I believe in addition to the extra 50mm, the 18-250 is just better glass. Haven't used it, but have liked the results I've seen from it. I understand the Sigma in this range is also good, but haven't seen anything from it. I doubt you can really go wrong with any of the 18-250's, whether it be Pentax, Tamron, or Sigma.

[henryjing]

I heard that Tamron lens is too sharp, you know, too sharp is not a good thing. But I have never used it, so just provide you a reference.

[epqwerty]

+1 for the 18-250mm if you have the funds for it. From what I hear it's a really really good lens.

[wjt]

OK, here are a few pics with the Tammy. The boat/beach ones are more of a FL thing, and i set it at 18mm and then took the photos at different FL.. so the latter ones aren't exposed properly (i didn't realise this till i got home) and SR was on for them all handheld.
so here they are, straight from the camera.

18mm, ISO 100, f11, 1/350


50mm, ISO 100, f11, 1/350


200mm, ISO 100, f11, 1/350


250mm, ISO 100, f11, 1/350


One from a recent holiday taken by the wife so it would have been P mode on the camera.
18mm, ISO 200, f14, 1/60

Hers turned out better than that ones i was taking.

Hope this was somewhat of a help

[little laker]

the latter ones aren't exposed properly (i didn't realise this till i got home) and SR was on for them all handheld.
so here they are, straight from the camera.

I hope that you don't mind, I took 2 seconds out to lightly post process 2 of them.

50mm, ISO 100, f11, 1/350



200mm, ISO 100, f11, 1/350


If I had better resolution images to start with I know that I could have done better.

Just play with the levels a little and you should see a big improvement.

[wjt]

yea, i probably should have done that before i posted it
i'll touch them up and fix them later tonight.

edit: fixed all the levels to the best of my somewhat limited ability.. in hindsight i should have just taken them properly, but i was very eager to play with my newest acquisition, the DA10-17mm Fish Eye .

[hcc]

I'm looking for a single lens to handle the 18-200 mm (or more) range. Basically, I want something for traveling to avoid having to haul around multiple lenses. I've narrowed the choices down to these:

Tamron 18-200mm f/3.5-6.3 XR DI-II LD Aspherical (IF) AF Zoom Lens with Macro (~$230, after rebate)
Sigma 18mm - 200mm f/3.5-6.3 DC Autofocus Aspherical Zoom Lens (~$300)
Tamron 18-250mm f/3.5-f/6.3 XR DI-II LD Aspherical (IF) AF Zoom Lens with Macro (~$470)

I've had good luck with Sigma lenses in the past, but never owned a Tamron, though I've heard a lot of good things about them. I'm sure there are more differences between these two Tamrons than just 50 mm of focal length, I just don't know what. And whatever the difference is, is it worth twice the price?

Any opinions on any of these would be greatly appreciated.

There have been several threads at www.Pentaxforums.com: search for 18-250mm.

The 18-200mm are older lenses. Their image quality is inferior to the newer 18-250mm. See the reviews in www.slrgear.com and www.photozone.de for example.

The best lenses are the Pentax DA18-250mm and Tamron 18-250mm. The DA18-250mm is simply a rebadged Tamron 18-250mm. Both Pentax and Tamron lenses have pretty identical performances and theh have excellent image quality peformances in their class. There have been several threads at www.pentaxforums.com on the Tamron vs Pentax performance. It is fair to say that everyone agree that the differences are very thin, as expected. A slight advantage of the DA18-250mm is that it is recognised by the K-7 and K-x cameras and the lens distortion correction may be applied on board.

There is a newer Sigma 18-250mm OS HSM. The price is more expansive than the 18-250mm. The OS (optical stabilisation) is not really needed since the Pentax cameras have on board IS (image stabilisation). The Sigma 18-250mm OS was really developed for the Canikon.

Hope that the comments will help ...

PS: I may add that the 18-250mm lenses (Tamron/Pentax) are in high demand. If you can find one around US$350-370, grab it; that would be a great deal.

[MrApollinax]

I am a happy Tamron 18-250 owner. For a superzoom it is a great lens as long as you understand what and where its strengths lie.

[GeneV]

There have been multiple threads on this topic. If you look at the test results, you see that the 18-250 performs about like putting the two kit lenses (18-55, 50-200) together, though with a bit more distortion at the wide end and a bit more reach at the tele. If you are happy with the performance of those lenses, you will be happy with one of the superzooms.

For the first year I owned a DSLR,the two kit lenses were the only digital zooms I owned, and I used the 18-55 for the vast majority of my shots-- only occasionally mounting the longer (50-200) zoom or a manual lens. I have personally not been tempted to replace the two kitters with one superzoom because of the extra weight on the camera. I have found that about 90% of my shots over the years fall in the DA 17-70 FOV range, and, if I am going to increase the bulk of the zoom around my neck while traveling, the extra size and weight is better used for some extra IQ or speed.

[phzy2003]

maybe you can get a 18-250 or get one 16-50 plus a 50-135. those big focal range lens usually don't have very good image quality

[glanglois]

My 2.5-year-old Tamrom 18-250 is somewhat soft at the long end, which is expected at the price. It's a consumer lens.

But I remain a bit unhappy about autofocus. It hunts, sometimes a lot, in dimmer light - like bright shade 2-3 hours before sundown. Sometimes it just gives up. Noon in bright shade is fine. Indoors is big challenge. If I get close with MF, then the AF usually will get back on track. Quick shift would be a godsend as I don't need the AF/MF change enough that it's fast and intuitive. Love it on my Pentax tele.

I understand that AF sensors are touchy when the aperture exceeds about f/5.6. The Tammy is f/6.3 at some point and that's when it hits the wall.

For reference, I observe this problem on both K10D and K-7 bodies. I have both.

For reference, I don't see this problem at all with the Pentax 55-300mm with a max of f/5.8.

That doesn't mean that I regret my purchase. Not at all. The lens is in my bag anytime I'll be shooting outdoors.

But as one more point in the discussion.