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07-24-2008, 06:33 AM   #121
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QuoteOriginally posted by leadbelly Quote
I just got my 16-50, and after a few test shots, it seems like a good copy. a few questions though...

1) Is the zoom ring really a little stiff, especially around 28-35mm? Unlike the 50-135 that's smooth? (Is it because of the weathersealing in the front part of the barrel where the lens extends?)

2) Focusing wide open is sharp at 50mm, but when I focus at 16mm, it's a little soft. Is this normal when used with the K10? (as with my 50-135, focusing is soft at the wide end, whereas focusing at the long end is hella sharp... but when I tried the 50-135 on a k20, it was sharp all the way.) Is this a K10D only issue?

Thanks!
1. I think is a temporally problem (silicone greasing). Your lens will work better after few times use. I'm not have this problem.

2. I think you must try to use your lens on K20D and watch the result. Probably it's problem K10D.

You're welcome!

07-24-2008, 08:22 PM   #122
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Some real world shots from my 16-50, is this a good copy? Serial number is 9024618...




I also just did a BF/FF issue test awhile ago, and at 50mm, it sightly back focuses. AF at 16mm though suffers from moderate BF... just like the 50-135, I'll just make it a habit to focus while zoomed in first, then zoom out to compose. Is this problem evident with the K20D? Or only with the K10D?

I also did a quick newspaper test (no tripod, not sure if its parallel), and it seems ok. With corner softness (as expected from a zoom), but not much. Center is sharp. Will do a more "scientific" newspaper test later though.

In all I think I got a good copy cept for slight back focusing. IQ is very much comparable with my 50-135 when sharp, and suffers from the same AF issues as its big brother (soft focus at wide end, have to focus zoomed in). Should I exchange my copy?

to add: with the K100D, it is just perfect. Is SDM really this inaccurate? Or should I learn to live with it?

Last edited by leadbelly; 07-24-2008 at 08:31 PM.
07-24-2008, 11:19 PM   #123
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A couple of wall shots of my 16-50, is my copy any good?
Focused on "mushroom" for both...

Here's on focused at 16mm


Another this time, focused at 50mm then zoomed out to 16mm


Keep or replace?
07-24-2008, 11:50 PM   #124
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QuoteOriginally posted by leadbelly Quote
Keep or replace?
I think is pretty well! Can you post link on the full-size of newspaper picture?

07-24-2008, 11:55 PM   #125
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QuoteOriginally posted by leadbelly Quote
Is SDM really this inaccurate? Or should I learn to live with it?
SDM works more well on the K10D after you flash v.1.3 bios. On the K20D its work good
07-24-2008, 11:57 PM   #126
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here...

http://farm4.static.flickr.com/3032/2700843538_e026c009e1_b.jpg

http://farm4.static.flickr.com/3046/2700842496_ed64c6b6db_b.jpg

any good?

What do you mean flash v.1.3 bios?
07-25-2008, 12:44 AM   #127
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QuoteOriginally posted by leadbelly Quote
any good? What do you mean flash v.1.3 bios?
Will see your photos after work (in my homeplace I have unlimited internet traffic)

Flash v.1.3 bios... I mean... Pentax releases firmware update version 1.30 for the K10D digital SLR camera.

With this latest firmware version the support for Pentax DA lenses with a built-in Supersonic Drive Motor (so called SDM lenses) has been implemeted.

Support for the Pentax SDM lenses has recently also been introduced with the announcement of Pentax's latest digital SLR camera, the K100D Super.

Update 1.30 for K10D you can download from PENTAX official site:

Software Downloads : Support & Service : PENTAX
07-25-2008, 12:47 AM   #128
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Link to firmware 1.30 for K10D (English):

http://www.pentax.jp/english/support/digital/firmware/k10e130w.exe

07-25-2008, 02:51 AM   #129
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ahh the firmware, yep. I already upgraded to 1.30. will try with the k20 latr to see if it backfocuses as well...
07-26-2008, 03:17 AM   #130
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QuoteOriginally posted by leadbelly Quote
well...
Your lens is good by my opinion
07-28-2008, 10:25 PM   #131
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Did a brick wall test...

I did a brick wall test, and I think mine has decentering defects The center is sharp, the left side is soft, but the right side is softer... I know there will will be corner softness, but both corners aren't the same, with the right side showing extreme softness...



I was initially fine with my copy's output, but after taking portraits, I found that people on the right side always looked soft. So I did the test. Is this reason enough for me to have it replaced or repaired?

edit: BTW, this is only one of many shots, all shots had the right side being soft. Parallel to the wall as well. Tried it with the 50-135, to see if maybe I wasn't parallel, the 50-135 was sharp across the frame...
07-28-2008, 10:41 PM   #132
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leadbelly,
I tend to agree with you on the right side being way to soft.
However I'm just wondering if it might not be quite perfectly parallel to the wall.
If I was doing the test I'd also aim it a little to the left, and then to the right. And see how it changes the image.

Plus I don't have access to the Image Data. To me it looks like this shot was taken around the 16mm mark.
If it was how about trying it around 18 and 20mm. And see if the problems still exist.

I know that at that price a lens should be perfect. But the reality is that it's still a zoom, so there's usually a compromise in IQ on one end or the other
07-29-2008, 07:32 AM   #133
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It was on a tripod and i made sure it was perfectly parallel, but still it came out soft... I'll try that tomorrow, the thing about aiming a little to the left and right...

It was taken at 16mm. I also shot at 50mm, it was still soft... what bugs me is that even in real world shots, the right side looks obviously soft...
07-29-2008, 08:41 AM   #134
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I do believe that you have a bad copy, I'd just rather see you out there enjoying a good lens than waiting for the same one to return if it's really alright.

I'm still not convinced that Tokina has their quality control issues fixed, with that one lens.
The odds of a good copy have gone up in leaps and bounds, however they're record still isn't what it should be.
07-29-2008, 08:13 PM   #135
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Updated list:

9010305 - GOOD
9011024 - GOOD
9011133 - GOOD - used from a forum member
9011582 - GOOD - from Amazon
9011592 - GOOD - from Digital Depot
9011905 GOOD
9012114 - GOOD -
9012269 - GOOD - from a Pentax retailer in Helsinkiin October
9012359 - GOOD - bought locally
9012509 - GOOD
9012537 - 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 Update fixed
9014376 - BAD - back focus
9014560 - GOOD
9014806 GOOD
9014888 - GOOD
9014xxx - BAD - slight de-centering and trouble focussing at 50mm (Reuben0)
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
9016531 - GOOD
9016577 - GOOD - from Henry's
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
9020323 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.
9021570 GOOD Beachcamera
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)
9024614 - GOOD
9024876 BAD
9025709 BAD Abes of Maine

49 out of 75 or 65%
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