Super soft edges on DA 15mm Ltd

stevebrot · 03-03-2016, 01:28 PM

Originally posted by hjoseph7

Maybe it's the way you guys are using this lens. This is a Super wide angle lens after all and not your regular 35mm wide angle. You may need to move closer to your subject so that it fills the frame.

I have shot with the DA 15 and have also seen many impressive images from many perspectives and the degradation evident in the OP's examples are not characteristic of that model regardless of subject distance.

Steve

**BigMackCam** · 03-03-2016, 02:58 PM

Originally posted by stevebrot

This is and the couple of other similar comments on this thread are disturbing. I wonder if there is a design weakness with the lens construction*.

Steve

* Stress break of the inner chassis that might affect both alignment and the focus distance sensing?

The DA15 is the only Limited prime using a hybrid aspheric lens element. I've just read another thread where de-centering issues were mentioned on a DA35 f/2.4 which also uses a hybrid aspheric element. Could be coincidence, but maybe there's a QC issue in this area of production...

**Digitalis** · 03-03-2016, 04:06 PM

Originally posted by BigMackCam

I've just read another thread where de-centering issues were mentioned on a DA35 f/2.4 which also uses a hybrid aspheric element. Could be coincidence, but maybe there's a QC issue in this area of production

Trying to cast doubt on the quality of polymer lens elements over glass ones are you? in any case: A 35mm f/2.4 lens would be unlikely to share an optical component with a 15mm f/4 lens.

**BigMackCam** · 03-03-2016, 05:08 PM

Originally posted by Digitalis

Trying to cast doubt on the quality of polymer lens elements over glass ones are you? in any case: A 35mm f/2.4 lens would be unlikely to share an optical component with a 15mm f/4 lens.

He he

No, certainly not

In any case, I've not had an issue with my DA35 f/2.4 or DA15 - but I was, rather liberally, wondering if there might be the potential for general production of hybrid elements to be subject to problematic tolerances / issues...

Nicolas06 · 03-06-2016, 01:46 PM

I had some issue with an old sample of my DA15. My new sample much better but not perfect. More than acceptable through. When I got the old sample for repair and paid for it, it didn't become any better.

The DA15 really has issues with lot of sample variation. Well all lenses have, but it seems there a greater share that are really bad with DA15, while most lense vary but less. I think this is a complex design.

You have to take the DA15 for what it is. It is extremely resistant to flare, very contrasty, comes with punchy colors. The rendering is unique and very interresting. The lense quite small. There no other UWA available to replace it. So that a trade of. you can buy a 8-16 from sigma (also some sample variation), you can buy a Samyang 16mm f/2 or Samyang 14mm f/2.8 but you'll get a huge thing that doesn't handle flare so well.

Depending of your priority, one choice is better than the other. For now, while I would have prefered to have a DA15 as sharp as an FA77, I know it is not possible for the size, and enjoy taking picture with it and keeping a light bag.

Beside the sample here is of the initial poster is quite bad, it was a good idea to send it back. Better to buy one new and ask the seller to exchange it if it a dud.

Few DA15 shots:

ntrao · 03-07-2016, 07:19 AM

Sending it for a repair will do any better in producing sharp images??

npc · 03-07-2016, 09:18 AM

Originally posted by Nicolas06

I had some issue with an old sample of my DA15. My new sample much better but not perfect. More than acceptable through. When I got the old sample for repair and paid for it, it didn't become any better.

Seems that way too many people (myself included) whent through few copies then settled for one that's "acceptable but not perfect" ... would be nice if somebody who believes his copy is "perfect" can post a full-sized/uncropped sample at f8 for reference.

kh1234567890 · 03-07-2016, 09:28 AM

Originally posted by npc

Seems that way too many people (myself included) whent through few copies then settled for one that's "acceptable but not perfect" ... would be nice if somebody who believes his copy is "perfect" can post a full-sized/uncropped sample at f8 for reference.

This I'll have to see ...

**clackers** · 03-07-2016, 09:15 PM

Originally posted by npc

Seems that way too many people (myself included) whent through few copies then settled for one that's "acceptable but not perfect" ... would be nice if somebody who believes his copy is "perfect" can post a full-sized/uncropped sample at f8 for reference.

Okay, I've put up a mundane snapshot SOOC, Npc, where's my prize?

Underneath it is a postprocessed, cropped version.

You have *632* pages of sample photos at https://www.pentaxforums.com/forums/122-lens-clubs/86234-15mm-limited-controls-my-mind-club.html that you would say is all a conspiracy - wonderful photographers like Hattifnat and Rondec are cropping not for composition, but to hide from the world performance so lousy they should get their money back from Pentax!

K-30, DA15Ltd, 1/100s, f8, ISO 800:

**BigMackCam** · 03-08-2016, 02:21 AM - **1 Like**

Originally posted by clackers

Okay, I've put up a mundane snapshot SOOC, Npc, where's my prize?

Underneath it is a postprocessed, cropped version.

The pixel 117 in from the left, 247 down is slightly blurred. Or is it? Well, either way, it must be decentered!

kh1234567890 · 03-08-2016, 02:42 AM

Originally posted by clackers

Underneath it is a postprocessed, cropped version.

Originally posted by npc

would be nice if somebody who believes his copy is "perfect" can post a full-sized/uncropped sample at f8 for reference.

**clackers** · 03-08-2016, 03:52 AM

Reading and comprehension not your strong points, KH?

The top one is as before - unprocessed, uncropped, and at f8.

As for claims that if you focus on something in the foreground, you won't be able to make out anything else in the scene, here's another snap.

(Kh1234567890, special note for the challenged, I'll say it slowly ... again the bottom one is postprocessed, the top one is the JPG Straight Out of the Camera).

**clackers** · 03-08-2016, 03:59 AM

Originally posted by BigMackCam

The pixel 117 in from the left, 247 down is slightly blurred. Or is it? Well, either way, it must be decentered!

Yes, Mike, the 'logic' is reminiscent of our old mate Osv - "I'm angry I bought a dud copy and didn't exchange it, so everyone's is a lemon, too".

kh1234567890 · 03-08-2016, 05:31 AM

Originally posted by clackers

(Kh1234567890, special note for the challenged, I'll say it slowly ... again the bottom one is postprocessed, the top one is the JPG Straight Out of the Camera)

But not full sized. All I see are Google-mangled 900odd pixel wide versions ...

npc · 03-08-2016, 09:14 AM - **2 Likes**

Originally posted by clackers

Okay, I've put up a mundane snapshot SOOC, Npc, where's my prize?

Underneath it is a postprocessed, cropped version.

You have *632* pages of sample photos at https://www.pentaxforums.com/forums/122-lens-clubs/86234-15mm-limited-controls-my-mind-club.html that you would say is all a conspiracy - wonderful photographers like Hattifnat and Rondec are cropping not for composition, but to hide from the world performance so lousy they should get their money back from Pentax!

Thanks, but these are some web-sized 870x576 pics not full-sized ... maybe I should have asked for a raw file instead to avoid confusion.

These *632* pages are full of scaled and cropped images as well, and I enjoy visiting them from time to time like the other lens clubs threads, but can't really be used as a reference if you wish to compare against the performance of your own copy. Something similar like OP's scene works well - there's enough fine texture (grass) all the way to the corners and you can in most cases find something similar to shoot with your own copy and compare.

The 15ltd suffers from poor corners, field curvature, decentering and sample variation - there's no conspiracy that can hide it

However, that's not the point - you can take great images with it if you learn how to compensate for these - OP's picture shows how bad a bad copy could be (and you don't even need a bigger size to see this) so I got curious how good a "perfect" one can be - but for this you need to do some serious pixel peeping, web-sized won't do.

03-07-2016, 09:15 PM	#39
clackers Otis Memorial Pentaxian Join Date: Jul 2013 Location: Melbourne Photos: Albums Posts: 16,397	Originally posted by npc Seems that way too many people (myself included) whent through few copies then settled for one that's "acceptable but not perfect" ... would be nice if somebody who believes his copy is "perfect" can post a full-sized/uncropped sample at f8 for reference. Okay, I've put up a mundane snapshot SOOC, Npc, where's my prize? Underneath it is a postprocessed, cropped version. You have 632 pages of sample photos at https://www.pentaxforums.com/forums/122-lens-clubs/86234-15mm-limited-controls-my-mind-club.html that you would say is all a conspiracy - wonderful photographers like Hattifnat and Rondec are cropping not for composition, but to hide from the world performance so lousy they should get their money back from Pentax! K-30, DA15Ltd, 1/100s, f8, ISO 800: Last edited by clackers; 03-07-2016 at 09:27 PM.

03-08-2016, 03:52 AM	#42
clackers Otis Memorial Pentaxian Join Date: Jul 2013 Location: Melbourne Photos: Albums Posts: 16,397	Reading and comprehension not your strong points, KH? The top one is as before - *unprocessed, uncropped, and at f8. As for claims that if you focus on something in the foreground, you won't be able to make out anything else in the scene, here's another snap. (Kh1234567890, special note for the challenged, I'll say it slowly ... again the bottom one is postprocessed, the top one is the JPG Straight Out of the Camera). Last edited by clackers; 03-08-2016 at 04:13 AM.*

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03-03-2016, 01:28 PM	#31
stevebrot Otis Memorial Pentaxian Join Date: Mar 2007 Location: Vancouver (USA) Photos: Gallery \| Albums Posts: 42,007	Originally posted by hjoseph7 Maybe it's the way you guys are using this lens. This is a Super wide angle lens after all and not your regular 35mm wide angle. You may need to move closer to your subject so that it fills the frame. I have shot with the DA 15 and have also seen many impressive images from many perspectives and the degradation evident in the OP's examples are not characteristic of that model regardless of subject distance. Steve

03-03-2016, 02:58 PM	#32
BigMackCam Digitiser of Film Join Date: Mar 2010 Location: North East of England Posts: 20,695	Originally posted by stevebrot This is and the couple of other similar comments on this thread are disturbing. I wonder if there is a design weakness with the lens construction. Steve Stress break of the inner chassis that might affect both alignment and the focus distance sensing? The DA15 is the only Limited prime using a hybrid aspheric lens element. I've just read another thread where de-centering issues were mentioned on a DA35 f/2.4 which also uses a hybrid aspheric element. Could be coincidence, but maybe there's a QC issue in this area of production...

03-03-2016, 04:06 PM	#33
Digitalis Site Supporter Join Date: Mar 2009 Location: Melbourne, Victoria Photos: Gallery Posts: 11,694	Originally posted by BigMackCam I've just read another thread where de-centering issues were mentioned on a DA35 f/2.4 which also uses a hybrid aspheric element. Could be coincidence, but maybe there's a QC issue in this area of production Trying to cast doubt on the quality of polymer lens elements over glass ones are you? in any case: A 35mm f/2.4 lens would be unlikely to share an optical component with a 15mm f/4 lens.

03-03-2016, 05:08 PM	#34
BigMackCam Digitiser of Film Join Date: Mar 2010 Location: North East of England Posts: 20,695	Originally posted by Digitalis Trying to cast doubt on the quality of polymer lens elements over glass ones are you? in any case: A 35mm f/2.4 lens would be unlikely to share an optical component with a 15mm f/4 lens. He he No, certainly not In any case, I've not had an issue with my DA35 f/2.4 or DA15 - but I was, rather liberally, wondering if there might be the potential for general production of hybrid elements to be subject to problematic tolerances / issues...

03-06-2016, 01:46 PM	#35
Nicolas06 Veteran Member Join Date: Nov 2013 Posts: 4,854	I had some issue with an old sample of my DA15. My new sample much better but not perfect. More than acceptable through. When I got the old sample for repair and paid for it, it didn't become any better. The DA15 really has issues with lot of sample variation. Well all lenses have, but it seems there a greater share that are really bad with DA15, while most lense vary but less. I think this is a complex design. You have to take the DA15 for what it is. It is extremely resistant to flare, very contrasty, comes with punchy colors. The rendering is unique and very interresting. The lense quite small. There no other UWA available to replace it. So that a trade of. you can buy a 8-16 from sigma (also some sample variation), you can buy a Samyang 16mm f/2 or Samyang 14mm f/2.8 but you'll get a huge thing that doesn't handle flare so well. Depending of your priority, one choice is better than the other. For now, while I would have prefered to have a DA15 as sharp as an FA77, I know it is not possible for the size, and enjoy taking picture with it and keeping a light bag. Beside the sample here is of the initial poster is quite bad, it was a good idea to send it back. Better to buy one new and ask the seller to exchange it if it a dud. Few DA15 shots:

03-07-2016, 07:19 AM	#36
ntrao Veteran Member Join Date: May 2009 Location: India Photos: Albums Posts: 384	Sending it for a repair will do any better in producing sharp images??

03-07-2016, 09:18 AM	#37
npc Veteran Member Join Date: Apr 2013 Posts: 313	Originally posted by Nicolas06 I had some issue with an old sample of my DA15. My new sample much better but not perfect. More than acceptable through. When I got the old sample for repair and paid for it, it didn't become any better. Seems that way too many people (myself included) whent through few copies then settled for one that's "acceptable but not perfect" ... would be nice if somebody who believes his copy is "perfect" can post a full-sized/uncropped sample at f8 for reference.

03-07-2016, 09:28 AM	#38
kh1234567890 Veteran Member Join Date: Sep 2010 Location: Manchester, UK Photos: Gallery Posts: 2,653	Originally posted by npc Seems that way too many people (myself included) whent through few copies then settled for one that's "acceptable but not perfect" ... would be nice if somebody who believes his copy is "perfect" can post a full-sized/uncropped sample at f8 for reference. This I'll have to see ...

03-08-2016, 02:21 AM - 1 Like	#40
BigMackCam Digitiser of Film Join Date: Mar 2010 Location: North East of England Posts: 20,695	Originally posted by clackers Okay, I've put up a mundane snapshot SOOC, Npc, where's my prize? Underneath it is a postprocessed, cropped version. The pixel 117 in from the left, 247 down is slightly blurred. Or is it? Well, either way, it must be decentered!

03-08-2016, 02:42 AM	#41
kh1234567890 Veteran Member Join Date: Sep 2010 Location: Manchester, UK Photos: Gallery Posts: 2,653	Originally posted by clackers Underneath it is a postprocessed, cropped version. Originally posted by npc would be nice if somebody who believes his copy is "perfect" can post a full-sized/uncropped sample at f8 for reference.

03-08-2016, 03:59 AM	#43
clackers Otis Memorial Pentaxian Join Date: Jul 2013 Location: Melbourne Photos: Albums Posts: 16,397	Originally posted by BigMackCam The pixel 117 in from the left, 247 down is slightly blurred. Or is it? Well, either way, it must be decentered! Yes, Mike, the 'logic' is reminiscent of our old mate Osv - "I'm angry I bought a dud copy and didn't exchange it, so everyone's is a lemon, too".

03-08-2016, 05:31 AM	#44
kh1234567890 Veteran Member Join Date: Sep 2010 Location: Manchester, UK Photos: Gallery Posts: 2,653	Originally posted by clackers (Kh1234567890, special note for the challenged, I'll say it slowly ... again the bottom one is postprocessed, the top one is the JPG Straight Out of the Camera) But not full sized. All I see are Google-mangled 900odd pixel wide versions ...

03-08-2016, 09:14 AM - 2 Likes	#45
npc Veteran Member Join Date: Apr 2013 Posts: 313	Originally posted by clackers Okay, I've put up a mundane snapshot SOOC, Npc, where's my prize? Underneath it is a postprocessed, cropped version. You have 632 pages of sample photos at https://www.pentaxforums.com/forums/122-lens-clubs/86234-15mm-limited-controls-my-mind-club.html that you would say is all a conspiracy - wonderful photographers like Hattifnat and Rondec are cropping not for composition, but to hide from the world performance so lousy they should get their money back from Pentax! Thanks, but these are some web-sized 870x576 pics not full-sized ... maybe I should have asked for a raw file instead to avoid confusion. These 632 pages are full of scaled and cropped images as well, and I enjoy visiting them from time to time like the other lens clubs threads, but can't really be used as a reference if you wish to compare against the performance of your own copy. Something similar like OP's scene works well - there's enough fine texture (grass) all the way to the corners and you can in most cases find something similar to shoot with your own copy and compare. The 15ltd suffers from poor corners, field curvature, decentering and sample variation - there's no conspiracy that can hide it However, that's not the point - you can take great images with it if you learn how to compensate for these - OP's picture shows how bad a bad copy could be (and you don't even need a bigger size to see this) so I got curious how good a "perfect" one can be - but for this you need to do some serious pixel peeping, web-sized won't do.