[pmolina]

good day all.. im new to this forum but have looked around and there seems to be a good mix of users.. so here goes. presently using a K5 with my go to lens being a tamron 28-75 f2.8.. it is definilty everything that everyone says it is.. however it does leave one wanting when it comes to shooting distant objects. (and sometimes cropping is not an option)... i do have a pentax-F 70-210, unfortunately havent used it much since its never with me when i need it. so im looking to maybe get something of an all around lense that i can keep on the camera and then revert back to the tamron when i know im going to be in close quarters and not need a superzoom. been reading reviews of the different lenses.. the pentax 18-270 (i know its a tamron)... the sigma 18-250 and the pentax 18-135.. the reviews so far of the pentax branded 18-270 are not good.. plus the $$$$ makes it a no go.. so my next option was the sigma.. reviews on this lens makes it a decent lense.. with good reach and $$$$ isnt too bad. .. then i read on the pentax 18-135.. so far i like what i have read and cost wise i guess ok.... IQ is more important than reach, but the sigma does have a decent amount more reach than the pentax. so the conundrum is ..... more reach , decent IQ, less $$$.. or less reach, better IQ, more $$$ and WR to boot... has anyone used both ..any opinion as to wish way you would lean..

[Tom S.]

Welcome to the forum! Have you looked in the lens database at these two lenses to see how users rated them? Personally, I would consider the 18-270 Pentax for the weather resistance, as I use my camera outside a lot, but that's a personal opinion based on absolutely no research on image quality.

[JinDesu]

Tom, I don't think the 18-270 has weather resistance? To my recollection, that was one of the complaints regarding the DA 18-270 with its high price. Did you mean the 18-135?

@Pmolina - If I had a choice, I would go with the DA18-135 over the Sigma 18-125. The Sigma's strength is in its silent focusing motor and it's relatively decent IQ for price. The DA 18-135 also has silent autofocusing motor and pretty good IQ overall. If I remember correctly, you can usually find the DA 18-135 for about $300 used on this forum, while the Sigma comes in at about $225-250. Given that price difference I would definitely go for the DA 18-135.

[kiwi_jono]

This depends a bit on your intended use:
* Do you need the reach to 270mm or is 135 enough?
* Do you want the lens to be fairly compact so its easy carry / travel with?
* What about WR - do you indent to shoot in poor weather or dirty environments?

I recently got a 18-135 WR and have to say I'm pretty impressed with it despite the varying reviews on it. Enjoying the relatively compact size, great autofocus and have been caught out in the rain a couple times recently and very pleased to have it.

[VoiceOfReason]

The Sigma 18-250 will give longer range, but I like the Pentax 18-135 due to WR, sharpness, quick and silent focusing, compact size, and color rendition.

[pmolina]

@tom s. Yeah.. doesnt help any in making my decision. ... actually makes it harder.

@JinDesu, Kiwi_Jono & Voice Of Reason.. i have been oh so slightly leaning towards the pentax 18-135 for the IQ and WR.. it will at least almost double my zoom from what i have now.. the more i read the harder it gets i have a few weeks before i pull the trigger and get one or the other ill keep an eye on the forum and see..

thanks to all so far for your opinion.

[Jaje67]

I had the 18-250 HSM and now have the 18-135 WR
I used the Sigma on Honeymoon part of which was a safari and had some excellent results. The lens is plenty sharp up toward the long end dropping off a wee bit at 250. Using the K5 high ISO gives you some latitude here to stop down to f8/11. It has brilliant min focus distance, decent macro ability and very quick AF.
I sold it when I returned home and bought the Pentax purely because I live in the N.E. of Scotland and need the WR. The Pentax is decentsharpness , quick and quiet AF though not as quiet as the Sigma I think it is just as quick. The Pentax has a much better build quality and is more compact, definately nicer to handle. I can recommend both but would say I would go for the Sigma for holidays (vacations if you are across the Pond) and I knew there was little to no chance of inclement weather. Having the WR allows you to take pictures at times and in places where other lenses would let you down . Either way you are going to get a good lens. Cheers

[pmolina]

@jaje67 : excellent ! thankyou.. ! cant say it makes my decision any easier (LOL) but i m glad to hear from someone that has used both.. i guess my decision will come down to zoom and how much i want WR.. thanks again!!

[Doundounba]

FWIW, you should also remember that Sigma recently announced a new version of their 18-200 in Pentax mount. Don't know if it's out just yet, but might be an interesting option...

[normhead]

We have both, the wife and I, I use the 18-135 all the time, the wife uses the 18-250 on occasion. Especially when she wants to go with the one body and one lens. I just feel the 18-135 is overall a better lens. Much of the time the 18-135 is a lens you won't take off the camera, even if you're carrying primes in the 20-50 range. The 18-250, not so much. But then I have the 60-250 to cover the long end so if I get something long I'm covered. We have excellent images taken with both.

Sigma 18-250 images..
http://s1132.photobucket.com/user/Norm_Head/slideshow/Pentax_forum/Sample_by...e/Sigma-18-250

DA 18-135 images
http://s1132.photobucket.com/user/Norm_Head/slideshow/Pentax_forum/Sample_by...name/DA_18-135

[kiwi_jono]

We have both, the wife and I, I use the 18-135 all the time, the wife uses the 18-250 on occasion. Especially when she wants to go with the one body and one lens. I just feel the 18-135 is overall a better lens. Much of the time the 18-135 is a lens you won't take off the camera, even if you're carrying primes in the 20-50 range. The 18-250, not so much. But then I have the 60-250 to cover the long end so if I get something long I'm covered. We have excellent images taken with both.

Sigma 18-250 images..
Sigma-18-250 Slideshow by Norm_Head | Photobucket

DA 18-135 images
DA_18-135 Slideshow by Norm_Head | Photobucket

Particularly like the 18-135 colour rendition in your shots. Would love to do a canoe trip like that some day!

[normhead]

Particularly like the 18-135 colour rendition in your shots. Would love to do a canoe trip like that some day!

Thanks for commenting... we love our trips, already two planned for the coming season.

[taxxl]

Hey everybody,

greetings from Germany and sorry for my English. ;-)

at the moment i have both lenses the DA 18-135 WR and the sigma 18-250 (old version).
I will sell my Sigma. Imho the Pentax is just a better lens (smaller, lighter, WR...). The only disadvantage i can see is that the focusing on the DA 18-135 is louder. But focusing in low light or low contrast is faster. In some cases where the Pentax gets in focus without any problems, the Sigma is just hunting for focus.

Another thing that i noticed when i tested the DA 18-135, is that the battery life with the DA 18-135 seems to be longer than with the Sigma 18-250. I don't have the passion and possibility to prove that.

I have used the Sigma on my K-r for more than a year. I like it. The Pentax is just better.

I tested both lenses on my K-30.

[tibbitts]

I don't understand the OP because the Sigma is obviously better from 135-250mm - the Pentax has a clear disadvantage there.

But the real comparison will be with the 18-300mm Sigma - I'll be interested to see how it fares vs. any of the pentax consumer zooms.

[K-Three]

I used to carry the Pentax 18-250 on my K5 all the time, then bought the K3 with the 18-135 kit, that is my carry around now, but I found I was missing the long end so I added the new 55-300WR.

Based on what you have now, I would recommend looking at adding the 55-300 and carrying two lenses. I have a small shoulder bag I carry every where with either the K5 or K3, with the 18-135 on it, and the 55-300 and the 35Macro and a bunch of other small stuff, it's not a big deal, and I have the tools I like to work with.
The 18-135 is a better, sharper lens than the 18-250, faster focus, less distortion, but I find it too short for a lot of the work I like to do.
If I was going out for the day, and only allowed one lens, I would probably go with the 18-135.

If IQ is important to you, you will get better results with two or more shorter range zooms than a single wide range lens. You need to decide if the convenience of one lens outweighs the potential quality of multiple lenses.

Another thought, You don't mention missing the wider end from your 28-75, both of the lenses you are thinking about will get you wider then you are currently achieving. Is it something you want/need?