[Muse]

I've seen conflicting information and nothing definitive. In fact I wonder if this is publicly known. Somebody knows, of course. People within Pentax know what the differences are, significant or otherwise.

Pentax represents it as an SMC lens, which presumably means it has their _proprietary_ lens coatings. However, it's often said that the Pentax version of this lens is just a rebadged Tamron. I've seen it said that the Pentax lens coatings are superior, but another poster said that the Pentax's lens coating looks different from the typical SMC coating on Pentax lenses, and he assumes that in reality it is the same coatings as on the Tamron version of the lens.

What do you think? Would you pay more for the Pentax version and if so, why?

[dgaies]

I've seen conflicting information and nothing definitive. In fact I wonder if this is publicly known. Somebody knows, of course. People within Pentax know what the differences are, significant or otherwise.

Pentax represents it as an SMC lens, which presumably means it has their _proprietary_ lens coatings. However, it's often said that the Pentax version of this lens is just a rebadged Tamron. I've seen it said that the Pentax lens coatings are superior, but another poster said that the Pentax's lens coating looks different from the typical SMC coating on Pentax lenses, and he assumes that in reality it is the same coatings as on the Tamron version of the lens.

What do you think? Would you pay more for the Pentax version and if so, why?

I've owned 2 copies of each lens (the Pentax and Tamron version) and as far as I can tell they are pretty much identical. I've also hear there may be a difference in the coatings, but I don't recall reading anything that fully substantiated that.

They each have a slightly different feel to them, but neither is really better, more of a personal preference. I did notice that the Tamron copies tended to have less zoom creep than the Pentax copies. That might mean nothing as it could be that I just had a couple tight copies of the Tamron and a couple of looser copies of the Pentax. Regardless, both versions will likely have some zoom creep and I personally found it to be a bit annoying as every time I tilted the camera down to review a photo, the lens would zoom out if I didn't remember to grip the zoom ring first.

One actual difference is that the Pentax version works with cameras that have in-body CA/Distortion correction. The Tamron version will not be able to use the CA/Distortion correction feature on the new DSLR bodies. This may or may not be a big deal for you.

[kytra]

i have the Tamron and it performs ok.

Pentax SMC DA 18-250mm f/3.5-6.3 ED AL [IF] - Review / Lab Test Report - Analysis
Tamron AF 18-250mm f/3.5-6.3 Di II LD Aspherical [IF] macro (Canon) - Review / Test Report - Sample Images & Verdict

pretty happy with it. I think I have a good copy

[vtqanh]

I don't think there's much different in terms of optical performance. And for what it's worth, the Pentax one has one year of warranty while the Tamron has six.

[dgaies]

I don't think there's much different in terms of optical performance. And for what it's worth, the Pentax one has one year of warranty while the Tamron has six.

Good point, although the Pentax (and probably the Tamron) have been discontinued for a while now so I don't think you can buy it new anymore.

[vtqanh]

In that case, it's even better to get the Tamron if you can find one that was purchased within the last few years

Good point, although the Pentax (and probably the Tamron) have been discontinued for a while now so I don't think you can buy it new anymore.

[hcc]

You already received some good feedback. There have been many threads and discussion on this topic. Let me try to summarise the key outcomes:

* the Pentax DA18-250mm was manufactured by Tamron based upon the Tamron 18-250mm

* both lenses are now discontinued but there are some excellent quality 2nd hand lenses available on the market.

* both lenses are highly regarded and considered among the best all round lenses (18-200mm & 18-250mm) among all brands incl. Canikon and co. See reviews in www.photozone.de, www.slrgear.com and in the Lens review of this forum:
Pentax SMC DA 18-250mm f/3.5-6.3 ED AL [IF] - Review / Lab Test Report
Tamron Lens: Zooms - Tamron 18-250mm f/3.5-6.3 Di II LD Aspherical IF Macro AF (Tested) - SLRgear.com!
SMC Pentax-DA 18-250mm F3.5-6.3 ED AL [IF] Lens Reviews - Pentax Lens Review Database

* both lenses are robust and sturdy; they do not have HSM which is an added bonus if you shoot in some rugged environments outdoor.

* the Pentax DA18-250mm is recognised by a number of recent Pentax camera bodies (K20, K-x, K-7) and in-camera lens distortion camera can be enabled. (This is not really an advantage; I owned a DA18-250mm and I never enable lens distortion correction: I prefer to PP the photo.)

* Some argued that the DA18-250mm yields better IQ, but there is honestly very little differences between both lenses.


In a few words:
+ If you want/need an all-rounder lens like a 18-250mm, go for it. You will not be disappointed by the Tamron/Pentax 18-250mm that is a leading lens in its own.
+ There is little difference between the Tamron and Pentax, and I would go for the cheaper price with identical lens conditions.

Hope that the comment will help...

---

Last edited by hcc; 09-04-2010 at 04:47 PM. Reason: Typos

[dgaies]

In that case, it's even better to get the Tamron if you can find one that was purchased within the last few years

Unfortunately, the Tamron 6-year warranty is only valid for the original buyer and isn't transferable to a second owner.

[Muse]

i have the Tamron and it performs ok.

Pentax SMC DA 18-250mm f/3.5-6.3 ED AL [IF] - Review / Lab Test Report - Analysis
Tamron AF 18-250mm f/3.5-6.3 Di II LD Aspherical [IF] macro (Canon) - Review / Test Report - Sample Images & Verdict

pretty happy with it. I think I have a good copy

One reason I'm looking at one of these for my first lens-only purchase (besides the unmatched versatility) is the apparent fact that the QA was reasonably good on them. I was initially drawn to the Tamron 28-75mm f2.8, but looking at a lot of user reviews I discovered that there are a lot of bad copies of that lens. I've read a lot of user reviews (close to 100, maybe more) of the Pentax and Tamron 18-250mm and remember only one where the user evidently had a poor copy in some respect. I'm a DSLR newbie and don't think myself qualified to evaluate the quality of a lens at this time. I posted a thread in the Lens Discussion Forum asking how to evaluate the quality of a used lens yesterday and Adam, the site webmaster, posted me a bunch of good tips. I printed it and have a copy in my pocket. The thread is here:

https://www.pentaxforums.com/forums/pentax-slr-lens-discussion/113089-how-can...used-lens.html

[Muse]

I've owned 2 copies of each lens (the Pentax and Tamron version) and as far as I can tell they are pretty much identical. I've also hear there may be a difference in the coatings, but I don't recall reading anything that fully substantiated that.

They each have a slightly different feel to them, but neither is really better, more of a personal preference. I did notice that the Tamron copies tended to have less zoom creep than the Pentax copies. That might mean nothing as it could be that I just had a couple tight copies of the Tamron and a couple of looser copies of the Pentax. Regardless, both versions will likely have some zoom creep and I personally found it to be a bit annoying as every time I tilted the camera down to review a photo, the lens would zoom out if I didn't remember to grip the zoom ring first.

One actual difference is that the Pentax version works with cameras that have in-body CA/Distortion correction. The Tamron version will not be able to use the CA/Distortion correction feature on the new DSLR bodies. This may or may not be a big deal for you.

I hadn't heard about the CA/Distortion correction functionality of certain Pentax cameras. I have the K-x, so I guess this could be an issue for me.

* both lenses are robust and sturdy; they do not have HSM which is an added bonus if you shoot in some rugged environments outdoor.

* the Pentax DA18-250mm is recognized by a number of recent Pentax camera bodies (K20, K-x, K-7) and in-camera lens distortion camera can be enabled. (This is not really an advantage; I owned a DA18-250mm and I never enable lens distortion correction: I prefer to PP the photo.)

Hope that the comment will help...

HSM = ? Hyper Sonic Motor?

I think that hcc means "in-camera lens distortion correction" there...

Why would this not be an advantage? Because PP is the better means of fixing the problem? That'll be new to me. Well, I'm partially color blind (total green blind = no green cones in my eyes), so I might be better off letting the camera correct CA than doing it myself in Photoshop. I have a copy of Photoshop Elements, but I haven't dealt with it yet.

The other distortions would be barrel distortion? Hmm, maybe I should lean to the Pentax. I'm hot on the trail of a Tamron and two Pentax's right now. Trying to bone up and sort out the issues so I make an informed decision. Thanks everyone for your help here!

[vtqanh]

You should be able to claim that it was gifted to you from the original purchaser (but of course you will need the original invoice)

"The Warranty shall not extend to anyone other than the original purchaser of the lens or the person for whom the lens was purchased as a gift."

Unfortunately, the Tamron 6-year warranty is only valid for the original buyer and isn't transferable to a second owner.

[hcc]

HSM = ? Hyper Sonic Motor?

Yes, HSM = hyper sonic motor.

The newest Sigma 18-250mm OS HSM has both OS and HSM. The lens received some nice users' comments in a number of threads, but the lens is pricy. Further OS is redundant to IS, while there have been a number of reports of HSM failure/incident with some lenses.

I am glad that the Pentax/Tamron 18-250mm does not have HSM: one less worry when I take the lens in the field.....

[RioRico]

* the Pentax DA18-250mm is recognised by a number of recent Pentax camera bodies (K20, K-x, K-7) and in-camera lens distortion camera can be enabled.

I've been using my K20D rather constantly for a couple years and have delved deeply into the manual, but I find nothing about lens distortion correction. I can correct distorted RAWs in PentaxPhotoLab3 but not in-camera. Or did I miss something somewhere?

[hcc]

I've been using my K20D rather constantly for a couple years and have delved deeply into the manual, but I find nothing about lens distortion correction. I can correct distorted RAWs in PentaxPhotoLab3 but not in-camera. Or did I miss something somewhere?

Both the K-7 and K-x have in-camera lens distortion correction. However I just checked the K20D manual and RioRico is right: the K20D does not have in-camera distortion correction. Mea culpa....

[Muse]

Both the K-7 and K-x have in-camera lens distortion correction.

I have a K-x. Has anyone tried the in-camera lens distortion correction feature? What is your experience? I know, this may be another thread or maybe I should run a search on it first. However, I think it's appropriate to ask here at this point. I have the 2 lens kit now (with 55-300mm), and maybe it would be useful there, but I'm especially curious about this vis a vis choosing between the Pentax and Tamron 18-255mm. This could be among the deciding factors when I acquire a lens, very possibly in the next few days. Or if the consensus is that it's more trouble than it's worth to turn on the feature, I'll not consider this a factor in making my decisions.