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Old 03-06-2008, 02:24 PM   #1
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New DA* 16-50mm...survey says....STINKER

On reports of more and more good copies I decided to pull the trigger on the 16-50mm and try my luck, I got it yesterday and 1st swing is a miss....

Back focus by about 18-20mm, big time sharpness issues on the left side of every image at 16/2.8 and still noticable at 4, and the right side was nothing to write home about. The kit lens trumped it in all tests. Must say I am a little bummed...I had high hopes. I tried every test, brick wall, newspaper, 45* focus test, and a bunch of "real world" shots wide open. What a hunk of expensive sh..... paperweight.

Luckily Amazon pays for return shipping, so I may have to try again. But still I must say the whole affair is totally unacceptable for a $700 item.

The SN was 9018018, since I know some are keeping track....

Wish me luck on #2.
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Old 03-06-2008, 03:00 PM   #2
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Originally Posted by bigben91682 View Post
On reports of more and more good copies I decided to pull the trigger on the 16-50mm and try my luck, I got it yesterday and 1st swing is a miss....

Back focus by about 18-20mm, big time sharpness issues on the left side of every image at 16/2.8 and still noticable at 4, and the right side was nothing to write home about. The kit lens trumped it in all tests. Must say I am a little bummed...I had high hopes. I tried every test, brick wall, newspaper, 45* focus test, and a bunch of "real world" shots wide open. What a hunk of expensive sh..... paperweight.

Luckily Amazon pays for return shipping, so I may have to try again. But still I must say the whole affair is totally unacceptable for a $700 item.

The SN was 9018018, since I know some are keeping track....

Wish me luck on #2.
That's a bummer. When you get a good one, they are superb.
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Old 03-28-2008, 05:54 PM   #3
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That sucks. Who makes that lens for pentax, is it tokina or sigma?
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Old 03-28-2008, 06:10 PM   #4
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Yeah, and since that first post I re-ordered from amazon and got another $700 paper-weight. I've given up for the time being. Looking for a used one that has been tested but that may be a tall order, 'cause once you get a good one, why sell it??
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Old 03-28-2008, 06:35 PM   #5
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Thats annoying. Why dont u try sending it straight to the manufacturer? better off letting them fix it i tihnk. But is it sigma or tokina that made the lens for pentax?
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Old 03-28-2008, 06:42 PM   #6
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tokina make a copy so maybe them?

are there any mailorder stores that will specially test a lens before they send it out?
if not, why not.
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Old 03-28-2008, 07:12 PM   #7
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I don't see how the Sigma would make this lens, since this is co-designed by Tokina only.

As for me, I just ordered the lens together with the K20D. If my copy turns out to be bad, I think I would send it to Pentax for them to fix it. I've not heard any fail attempt from Pentax.
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Old 03-28-2008, 07:17 PM   #8
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I dont recall stating sigma or tokina as the manufacturer.
I do however recall asking who was
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Old 03-28-2008, 10:22 PM   #9
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Originally Posted by dmadden View Post
I dont recall stating sigma or tokina as the manufacturer.
I do however recall asking who was
The design was done in cooperation with Tokina for a number of the lenses. If the lens on a Tokina advert has the same specs as the Pentax lens, it's the same optical formula. The Pentax lenses have the Pentax coatings. I have not seen both to compare mechanical build quality. Both my DA* lenses are great. Very happy with them. Lucky me. First try, too.

IMHO, if the lens were bum, I'd send it to Pentax and get it fixed right rather than hassle with trying out lens after lens.
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Old 03-28-2008, 11:24 PM   #10
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Da* 16-50 can be daunting with backfocusing on k10d. On k20d, it is actually quite a performer. I get less hunting with AF and it is becoming a pleasure to use.
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Old 03-29-2008, 01:15 AM   #11
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I'm using it on a K100D, so the DA* is run on the screwdrive not the HSM. Mine has actually been refurbished and recalibrated by Pentax.

There's the occasional non-focus problems, but this one is definitely a lot better than the other 4 I tried, each one in different stores/conferences. I'm still really happy with it and it's 98% of the time bang on (and if not, I adjust with the manual focus ring). Coupled with the Pentax flash, this lens shines.

I've noted some purple-fringing (CA) wide open, and the F2.8 is a bit soft (nothing like my DA and M primes. those things are pretty sharp wide open) but overall it's still a good lens that can take good pictures. I've learned to live with it's faults so far....I consider them part of the character of the lens. But that being said, there are a few copies of this lens that seriously need some work (as was the case of the first 4 that I tested... and didn't buy).
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Old 03-29-2008, 02:58 AM   #12
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I'm guessing it's a Tokina.

Hmmm. The Tokina even claims to have a special coating to repel "water or fingerprints."

It's sad that a flagship lens is actually, pretty much, not a Pentax save for a few bits on the outside. And, clearly this is something Pentax needs to address.

There're also a lot of lenses on the Tokina page that make me really wonder who's making them for Pentax - there's a 35mm f2.8 macro, a 12-24 f4 ultrawide, a 50-135...

Very depressing. Do Pentax still make any lenses? It seems a clear-cut case of dodgy outsourcing.
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Old 03-29-2008, 05:35 AM   #13
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Originally Posted by lithos View Post
I'm guessing it's a Tokina.

Hmmm. The Tokina even claims to have a special coating to repel "water or fingerprints."

It's sad that a flagship lens is actually, pretty much, not a Pentax save for a few bits on the outside. And, clearly this is something Pentax needs to address.

There're also a lot of lenses on the Tokina page that make me really wonder who's making them for Pentax - there's a 35mm f2.8 macro, a 12-24 f4 ultrawide, a 50-135...

Very depressing. Do Pentax still make any lenses? It seems a clear-cut case of dodgy outsourcing.
As far as I can remember, Pentax as always outsourced the manufacturing of some of it's lenses, if not all.
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Old 03-29-2008, 10:26 AM   #14
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This is really interesting. Where have you guys been? It has been stated MANY times that the lens was co developed with tokina and manufactured in Pentaxes plant in Vietnam. My first copy had the usual problems of not focussing at the 16 to 24mm range. I had my dealer send it to Pentax for warrenty repair and 3 weeks later they sent me a brand new lens. This one seems to be steller.
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Old 03-29-2008, 10:51 AM   #15
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hope you get a better copy.
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