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Old 04-29-2008, 01:34 PM   #61
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One more on the bad side

Serial number 9018897 purchased from Amazon - sent to service center today
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Old 05-05-2008, 07:45 PM   #62
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Got my one from adorama and obviously it is not a very good copy. At 2.8 and 16mm I have to take a couple of shots to get a sharp image. At 16mm and 4.5 everything is fine.

Serial number is 9019078.

Itīs ridiculous what pentax is doing. After that long time I thought everything should be fine now, but itīs not, and they didnīt even recall all the lenses. Why? Instead of recalling, they brought the K20D which has the focus correction thing. How stupid is that?
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Old 05-07-2008, 09:46 PM   #63
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serial # 9011582 bought from Amazon in Oct'07
did all kinds of test, and realised i was suffering from users errors
and thru the pics i got from it , i got a great copy
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Old 05-11-2008, 04:33 AM   #64
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good one

i got mine at a camera shop here in nagano japan. it has been fine.

9016508
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Old 05-11-2008, 07:46 AM   #65
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Calumet NYC Store.

Did numerous test shots in store before buying, did a walk around during for remainder of lunch period, did more samples at home.....showed Codiac2600 to get his thoughts......

we both concluded......good copy
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Old 05-11-2008, 11:08 PM   #66
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Originally Posted by Denny View Post
Got my one from adorama and obviously it is not a very good copy. At 2.8 and 16mm I have to take a couple of shots to get a sharp image. At 16mm and 4.5 everything is fine.

Serial number is 9019078.

Itīs ridiculous what pentax is doing. After that long time I thought everything should be fine now, but itīs not, and they didnīt even recall all the lenses. Why? Instead of recalling, they brought the K20D which has the focus correction thing. How stupid is that?
The "focus correction thingy" you allude to is actually a feature to correct AF lenses that have a tendency to BF or FF. Nikon and Canon also have this feature on their *top* spec models like the D300 and 1DS MKII etc as they *also* have BF and FF issues. We should be thankful that Pentax have seen fit to include it in a model costing alot less than these two examples.

Lens BF and FF issues are quite common in *all* manufacturers lenses and there have been many threads dedicated to these problems on forums of *all* camera manufacturers.

The DA*16-50 f2.8 has some issues, yes, but they need to be taken in context when compared to other manufacturers. This of course doesn't absolve Pentax from trying to have the best QC they can, but also do not unfairly denegrate Pentax as if they are the only ones with QC issues with BF/FF in their lenses.

The interesting thing to remember is that a zoom may focus fine at one end of the zoom range but not be so good at the other end. This phenomenon can be again also evident across *all* manufacturers. The reason *may* lie in the fact that the different colour wavelenghts of light converge at different points - chromatic aberration - and in a zoom this all the more a problem as because when you alter focal length, the the design parameters that were used to fix chromatic aberration at one focal length may not work for others. Zooms are therefore a compromise and the more there is a difference between the short end and the long end of a zoom range, the more there maybe a problem.
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Old 05-12-2008, 05:57 AM   #67
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OK, after reading all the reviews and users' experiences I have decided to try my luck and ordered a refurbished one from Warehouse Deals (Amazon.com) for $553.

It arrived on May 7. Funny enough, it is the same lens as already tested by bigben91682 and returned back to Amazon. The serial # is 9018018.

I gave it a try yesterday, and I can say that it is meeting my [tough] standards.

Although primes will beat this zoom in resolution, the image quality of my copy of the 16-50 is very high. No BF, no FF, and image is sharp. There is a reasonable drop in quality on the edges and some CA, but nothing to worry about.

So, it is GOOD!

It may be well that this lens was sent back to Pentax to fix the issues reported by the previous owner.

Last edited by 6x9; 05-12-2008 at 08:06 AM..
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Old 05-12-2008, 10:57 AM   #68
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Just got the 16-50 from warehouse deals... worried now after reading this thread. It was a OMG it's only 570 shipped!! impulse reaction... Will let you guys know soon since I have amazon prime and did next day
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Old 05-12-2008, 11:08 AM   #69
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S/N 9019329 bought from Adorama.

So far I haven't noticed any focus-problems. Have done the focus test chart etc. I'm interested in what has been the issue with the bad ones (besides BF/FF), someone who can explain??

/jesper
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Old 05-12-2008, 02:59 PM   #70
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Originally Posted by JKS View Post
S/N 9019329 bought from Adorama.

So far I haven't noticed any focus-problems. Have done the focus test chart etc. I'm interested in what has been the issue with the bad ones (besides BF/FF), someone who can explain??

/jesper

Good copy: 9015662 bought at National Camera and Video, Edina, MN.

I had two copies before my third (excellent) copy. The first was blurry at all focal lengths. The second was very sharp, good focus speed, etc in good light, but missed focus 50% of the time in tungsten lighting - BF mostly. The third still misses focus in dim tungsten lighting, but maybe only 10% of the time - about the same rate as my other lenses, including the FA 50 1.4, etc.

Except for those 10% of dim tungsten shots, this third copy is absolutely stellar and a thrill to use.

Here's what you can expect from a good one:

---> Picasa Web Albums - Jay - DA_16_50

---> DA* 16-50 in the American West



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Old 05-15-2008, 10:53 AM   #71
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9011592 from Digital Depot.
Once I'd mastered autofocus ( which was new to me coming as I did from an OM1) and accepted its limitations I found this 16-50 to be excellent.
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Old 05-18-2008, 10:16 AM   #72
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Update

9019346 from Willoughby's is bad

Auto-focus will either take a few seconds before it will work or won't auto-focus at all. I have already cleaned the connectors a few times. Sometimes, the lens will work without any problems. The auto-focus failure has happened while shooting indoor and outdoor.
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Last edited by thear; 05-18-2008 at 07:01 PM..
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Old 05-18-2008, 12:32 PM   #73
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Originally Posted by 6x9 View Post
OK, after reading all the reviews and users' experiences I have decided to try my luck and ordered a refurbished one from Warehouse Deals (Amazon.com) for $553.

It arrived on May 7. Funny enough, it is the same lens as already tested by bigben91682 and returned back to Amazon. The serial # is 9018018.

I gave it a try yesterday, and I can say that it is meeting my [tough] standards.

Although primes will beat this zoom in resolution, the image quality of my copy of the 16-50 is very high. No BF, no FF, and image is sharp. There is a reasonable drop in quality on the edges and some CA, but nothing to worry about.

So, it is GOOD!

It may be well that this lens was sent back to Pentax to fix the issues reported by the previous owner.

I want it back then.... :-D
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Old 05-18-2008, 03:48 PM   #74
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Despite naysawers I had to do it as I know I would regret not trying . Last week went to McBain Camera they had 4 in stock. First one was not that impressed with, second one seemed to be a keeper. I have used it quite a bit last week and I have passed my 7 day return no questions asked. I still have another week for a repalcement but really I have used it enough I have no compliants.

Serial number 9016652

Interstingly the first one was 90163xx both are early models (Janurary 08) but I am happy with mine.
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Old 05-19-2008, 09:26 PM   #75
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I had reported a problem with Serial number 9018897. I sent it into repair service, which they asked me to send in my k10D. Received both back today - everything is wonderful. Focus is exactly on. I suspect there was some software tweaking on the camera body but frankly I don't know if I care. I'm just happy to have it back and working.
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