[Derridale]

Hi Tbear

I wasn't having a go at you - I was merely trying to point out that to prove the problem, the test needed to be done rigorously.

You obviously did do it that way, and Pentax obviously agreed with you.

However, the test CAN be misleading, as another poster pointed out - that's all.

[Tbear]

Hi Tbear

I wasn't having a go at you - I was merely trying to point out that to prove the problem, the test needed to be done rigorously.

You obviously did do it that way, and Pentax obviously agreed with you.

However, the test CAN be misleading, as another poster pointed out - that's all.

No offense taken, Pete. You are quite right that it is very easy to perform a flawed test.

[jgredline]

The point is simply this as far as I go.
I purchased a DA*16-50mm lens and quickly noticed that it was very soft of both ends at f/2.8...I took it back and exchanged it for another one...This one was soft only on the left side of the photos which was strange to me and still soft at, to soft at 50mm...
I know nothing of tests or having to test a lens for that matter. I only what I see with my eyes and my eyes were telling me that my Kit lens 18-55mm cheapo was allot sharper all the way around...My third lens is in finally, so I will be picking it up this afternoon...I will be showing up with camera and LAP top in hand...If it is still no good, I will simply get credit and put it twords the new bodies when they come in..

[Tbear]

The point is simply this as far as I go.
I purchased a DA*16-50mm lens and quickly noticed that it was very soft of both ends at f/2.8...I took it back and exchanged it for another one...This one was soft only on the left side of the photos which was strange to me and still soft at, to soft at 50mm...
I know nothing of tests or having to test a lens for that matter. I only what I see with my eyes and my eyes were telling me that my Kit lens 18-55mm cheapo was allot sharper all the way around...My third lens is in finally, so I will be picking it up this afternoon...I will be showing up with camera and LAP top in hand...If it is still no good, I will simply get credit and put it twords the new bodies when they come in..

Hope the third one works out for you, Javier. Let me know either way.

Ted

[jgredline]

Ted
I picked up my 3rd DA*16-50mm and whala, third time is a charm..Works perfectly.
It's dark and gloomy outside so in fairness, I will take some more photos tomorrow and post them....But this one is indeed better than my kit lens...

[Tbear]

As some of you may or may not know, I purchased a DA*16-50 earlier this month. When I received it, I performed a newspaper test, comparing it to my kit lens, which I have never had a problem with. The images demonstrated a centering defect in the * lens, rendering most of the images inferior to the kit lens. This defective brand new lens was sent to Pentax USA in Westminster Colorado at my expense. Pentax neither admitted or denied that there was a problem with the first * lens. They sent me a new DA*16-50mm lens, so I am assuming they did find a problem with it. Interestingly, the replacement had a serial number that was smaller than the defective lens I sent in (9016XXX----->9013XXX).

Well, I just finished performing the identical test on the second DA* 16-50 lens, comparing it to my venerable kit lens. The * lens again demonstrated inconsistent sharpness across the newspaper with overall poorer sharpness than the kit lens at identical focal lengths and aperture. I rate this lens to be no better or no worse than the lens that Pentax subsequently replaced. I have lost all confidence in the quality of this lens. I don't want to waste any more time and money sending Pentax's junk lens back and forth the USA. The Pentax customer service representative was courteous and once I had explained the situation, he told me he would immediately bump it up to management level. He said I can expect a call from Pentax by tomorrow to resolve the matter.

[TomInJax]

Well, I just finished performing the identical test on the second DA* 16-50 lens, comparing it to my venerable kit lens. The * lens again demonstrated inconsistent sharpness across the newspaper with overall poorer sharpness than the kit lens at identical focal lengths and aperture.

Hmmm... I am not going to get one. I don't want to have to go through what you and others are having to do. I and others will probably hesitate at buying a used one, thinking that it might be another lemon!

I hope that Pentax understands that this is costing them sales and reputation! I hope that it doesn't get to be as bad with their new products. Many people are lusting after the new DA* lenses that Pentax is coming out with. All it will take to destroy Pentax's reputation and ruin their small share of this market, is to come out with a crap DA*300 too!

The DA* 16-50 was on my list. But now I don't think that it will happen now.

[Tbear]

Hmmm... I am not going to get one. I don't want to have to go through what you and others are having to do. I and others will probably hesitate at buying a used one, thinking that it might be another lemon!

I hope that Pentax understands that this is costing them sales and reputation! I hope that it doesn't get to be as bad with their new products. Many people are lusting after the new DA* lenses that Pentax is coming out with. All it will take to destroy Pentax's reputation and ruin their small share of this market, is to come out with a crap DA*300 too!

The DA* 16-50 was on my list. But now I don't think that it will happen now.

From everything I can glean, it seems that the DA* 50-135mm is a much better designed and manufactured lens. I have read an enormous number of rave reviews on this lens and very very few bad ones. So hopefully, the DA*16-50 is the only "bad" * lens of the lot. I realize that many people are happy with the copy of the DA*16-50 that they received and I am truly happy for them. It is my opinion that there is a design or manufacturing flaw with this lens that makes it more susceptible to problems than most lenses.

[bentax]

i REALLY want this lens but looks like i'm going to have to wait for some legit news of the qc issues being dealt with before getting one shipped halfway across the world.
i'd imagine alot of people are in the same boat.

[wlachan]

From everything I can glean, it seems that the DA* 50-135mm is a much better designed and manufactured lens. I have read an enormous number of rave reviews on this lens and very very few bad ones. So hopefully, the DA*16-50 is the only "bad" * lens of the lot. I realize that many people are happy with the copy of the DA*16-50 that they received and I am truly happy for them. It is my opinion that there is a design or manufacturing flaw with this lens that makes it more susceptible to problems than most lenses.

Testing a wide-standard zoom with a 2D target at close range can generate misleading results if not done very very precisely. I have been through this route. I strongly suggest you do some actual shooting, scenery preferred before you draw your final conclusion.

[heatherslightbox]

I know it's got to be disappointing that neither lens worked out for you. If I was going to get one of the *zooms, it would've been that one, but with all the issues other people have had with it, I don't know...perhaps Pentax will decide to go back to the drawing board with this one.

Not too long ago, I read a posting on the dpreview Pentax SLR forum where someone had contacted Tamron directly to ask them if they had any plans to come out with the DiII 17-50/2.8 LD in the Pentax mount and the response was that they're considering it, but nothing is definite. From what I understand, it's supposed to be a pretty decent lens. Another poster suggested that anybody who's interested in this lens contact Tamron to voice their opinion. Perhaps if enough Pentaxians want it, then they'll go ahead and produce it.

If Tamron does decide to come out with this lens in the Pentax mount, then that would be another option in the wide zoom/constant aperture category that's not terribly expensive for what you get-- B&H has it for $424 after rebate in the Canikon and Sony/Minolta mounts.

We'll keep our fingers crossed.

Heather

[Tbear]

Testing a wide-standard zoom with a 2D target at close range can generate misleading results if not done very very precisely. I have been through this route. I strongly suggest you do some actual shooting, scenery preferred before you draw your final conclusion.

You are absolutely right, Alan, that the test must be done with great precision to be sure. If you were with me to watch the whole testing process and looked at the results, you would have NO doubts left. Meanwhile, Pentax told me they would repair or replace the DA*16-50 as they saw fit. Well, they saw fit to send me a new lens (at least one with a different serial number). That should lend some degree of credibility to my testing methods. Would they have done this if there was no problem with the lens, without so much as a word from them?

[Tbear]

I know it's got to be disappointing that neither lens worked out for you. If I was going to get one of the *zooms, it would've been that one, but with all the issues other people have had with it, I don't know...perhaps Pentax will decide to go back to the drawing board with this one.

Not too long ago, I read a posting on the dpreview Pentax SLR forum where someone had contacted Tamron directly to ask them if they had any plans to come out with the DiII 17-50/2.8 LD in the Pentax mount and the response was that they're considering it, but nothing is definite. From what I understand, it's supposed to be a pretty decent lens. Another poster suggested that anybody who's interested in this lens contact Tamron to voice their opinion. Perhaps if enough Pentaxians want it, then they'll go ahead and produce it.

If Tamron does decide to come out with this lens in the Pentax mount, then that would be another option in the wide zoom/constant aperture category that's not terribly expensive for what you get-- B&H has it for $424 after rebate in the Canikon and Sony/Minolta mounts.

We'll keep our fingers crossed.

Heather

Thank you for your kind sentiments.

[Kguru]

Well, they saw fit to send me a new lens (at least one with a different serial number). That should lend some degree of credibility to my testing methods. Would they have done this if there was no problem with the lens, without so much as a word from them?

I suspect Pentax has a pool of these returned lenses, makes some adjustments then circulates them back to the market. In other words your 9013xxx is a refurbish from someone earlier and your 9016xxx will be for someone in the future. It's no hardship to send out one to keep you happy for now.

[jbcampbell]

It took me 4 copies to get a good one. Now, I didn't do any newspaper tests, I just shot my normal subject matter at various F-Stops & examined the results. The last (#4) one I got was sharp wide open & got better from there at all focal lengths.

Good luck & let us know what Pentax says, when I called they wanted me to send the lens & my K10D together for examination. That didn't happen I just kept exchanging the lens until i got a good one ;-)