DA* 16-50mm Serial Number Database.

[Joseph D.]

9306 - not that great... Had to adjust -7 and then noticed the lens seemed to be sharp in the middle to top left but blurry on the bottom right. Also couldn't focus to infinity.

7198 - on the other hand, seems fine. 0 adjustment. No noticeable focus issues yet on real life targets (kids playing around - haven't had a chance with the focus chart yet). Alignment seems fine. Will test more this weekend (brickwall, etc..). It snaps to infinity without hesitation.

Purchased in Vancouver, Canada. First one in early May the replacement just a few days ago.

Hope this helps.

Joseph

[thear]

Update

9013490 is another bad lens

The lens has aperture problem. When shooting at f/4-f/22, photos are over exposed. Photos become more over exposed as the aperture is being stopped down further. I'm not satisfied with Pentax's service center. I sent in my lens for repairs in like new condition, the replacement lens I received had some wear, a small dent, and it was dirty. I have sent my gear to Pentax's service center in the past, I have always received the same equipment back. I was under the impression that I will be given a "new" lens, based on the email I received below.

Thank you for contacting Pentax.

We are replacing your lens with a new one. It should be shipping out today or tomorrow via UPS ground.

If you are in need of further assistance, please respond to this email or call our technical support center at 800-877-0155.

[jms698]

s/n: 9010305

(probably the earliest serial number of all the lenses listed here; bought from Photography and Electronics Stores - We are experts in all the products we sell. )

good! slightly soft at the corners at f/2.8, but otherwise excellent throughout on the K20d.

[Beau]

9021501 -- seems to be good at first sight, a bit soft wide open at 16mm in the corners. Bought at fotokonijnenberg, turnhout, belgium.

Seems like the newer 902... serials are all good up to now.

update
--------

I uploaded some testshots. Could someone with a good copy take a look and tell me if I got a good one?
Picasa Web Albums - Beau - DA* 16-50 f2....

[Reuben0]

Originally Posted by Beau

Seems like the newer 902... serials are all good up to now.

??? That's not what I would conclude reading back through the posts...

R

[Beau]

Originally Posted by Reuben0

??? That's not what I would conclude reading back through the posts...

R

You are correct, some bad 902s are reported in the later pages.

[GoSharks]

9018278 from Beach Camera (6/13) seems good so far, apart from a little stickiness in the zoom action at 28mm going from 16->50.

[kokanee]

Hi fellow pentaxians,
as it seems is my lens a good one. It's somewhat soft on the edges at f2.8, but generally I'm happy with it.
SN: 9014560
Greetings from southern Bavaria,
Peter

[Prognathous]

Updated list:

9010305 - GOOD
9011024 - GOOD
9011133 - GOOD - used from a forum member
9011582 - GOOD - from Amazon
9011592 - GOOD - from Digital Depot
9012114 - GOOD -
9012269 - GOOD - from a Pentax retailer in Helsinkiin October
9012537 - GOOD -
9012359 - GOOD - bought locally
9012509 - GOOD
9012541 - BAD - from Amazon, beginning of January
9012612 - BAD - from Keeble and Shuchat in Palo Alto, CA (focus is fine, but suffered mechanical failure)
9013067 - GOOD
9013124 - BAD
9013251 - GOOD
9013254 - BAD
9013269 - GOOD - from ACE Photo - Northern Virginia
9013490 - BAD - aperture problem
9014xxx - BAD - slight de-centering and trouble focussing at 50mm (Reuben0)
9014376 - BAD - back focus
9014560 - GOOD
9014888 - GOOD
9015311 - BAD
9015662 - GOOD - from National Camera and Video, Edina, MN.
9015921 - BAD - from a hometown store
9016333 - BAD
90163xx - BAD - reported by daacon
9016410 - GOOD - from CameraWarehouse.com.au
9016499 - GOOD
9016508 - GOOD
9016577 - GOOD - from Henry's
9016531 - GOOD
9016652 - GOOD - from McBain Camera
9016761 - BAD
9017115 - GOOD
9017198 - GOOD - purchased in Vancouver, Canada
9017292 - BAD - from B&H
9017473 - GOOD - from a local store in Canada
9017525 - BAD - So it's a BAD copy on K10D, but a GOOD one on K20D
9017549 - GOOD - from Digit-Photo in December
9017856 - GOOD
9018018 - BAD - from Amazon (new, first owner)
9018018 - GOOD - from Amazon (refurbished, second owner - fixed by Pentax?)
9018137 - BAD - from Amazon03-17-2008
9018176 - BAD - from Adorama
9018278 - GOOD - from Beach Camera
9018380 - BAD - from B&H
9018546 - GOOD
9018897 - BAD - from Amazon (now that Pentax fixed it, it's GOOD)
9018946 - GOOD -
9019078 - BAD - from Adorama (not very good, focus at 16/2.8 unreliable)
9019218 - GOOD - from Adorama
9019284 - GOOD - from Adorama
9019306 - BAD - purchased in Vancouver, Canada.
9019329 - GOOD - from Adorama
9019346 - BAD - from Willoughby's (originally reported as good, but now refuses to focus)
9019612 - GOOD
9019818 - GOOD
9020266 - GOOD
9021116 - GOOD - from B&H (focusing may be "a tad off")
9021117 - GOOD
9021232 - GOOD - from Willoughby's
9021501 - GOOD - from fotokonijnenberg, Turnhout, Belgium.
9022439 - GOOD - from Calumet NYC
9023236 - GOOD - from SRS Microsystems
90233xx - BAD - total rubbish in the corners unless stopped down to F16 (Reuben0)
9023463 - GOOD - from buydig
90244xx - BAD - corner softness, tested briefly in the shop (Reuben0)
9024876 - BAD

Prog.

[milans]

Bought today 9020323 in Fotobesenicar - Slovenia for now looks good I hope also in the future...

[sinus007]

9021570 is OK. Bought it from Beachcamera a week ago. Did a few crude tests.

[morfic]

Thanks Prognathous.

Any more nicks to the Bad lenses? or is Reuben0 the only "unlucky" guy?

When people repeatedly find "bad lenses" i wonder if it says more about the lenses or the users.

[iunknown]

Originally Posted by GoSharks

9018278 from Beach Camera (6/13) seems good so far, apart from a little stickiness in the zoom action at 28mm going from 16->50.

I have experienced the same situation. The lens seems to be good so far. There is some stickness (a little) near 28mm. I bought this lens from B&H. My previous one from Abes Of Maine was bad and I had to return it. The serial number is 9025709

One thing I noted is this serial number seems to be from the 2008 batch and my previous 16-50 got from Abes was 2007 batch..

-IU

[thear]

Update

9013490

Received the lens from repairs a week ago, problem has been fixed. I did not perform a thorough IQ test yet.

[fishy]

9029381, received just today from Adorama.
Not too sure. Focus is lovely quiet, but it seems soft @ 2.8. Can anyone with a good lens post a sample? here's one (K10D):
100iso, 2.8, 1/50, 50mm (100% crop).
@16 it is noticeably better. What do you guys think?