Question for 16-50mm owners

morfic · 05-31-2008, 07:39 PM

It's threads like these that make me s**t my pants when i go browse for 16-50 in stock, i wouldn't mind the price for what i should be getting, i just don't want to be another statistic by picking up my first bad Pentax lens.

Hey! did you just remove the 16-50 from your signature? ;P

Either way, i will have to have a really close look at my non-pentax 2.8 zoom thread and hopefully whatever i will decide is going to work for me in the end.....i just wish these threads (and the associated problems) didn't exist

PentaxPoke · 05-31-2008, 07:52 PM

You are amazingly observant! Yes I did remove it. Also, your non Pentax 2.8 thread is very timely. Oh, and the first sentence of your post above, is exactly the way I felt. Unfortunately, I ended up a statistic.

I do like my 50-135 though.

morfic · 05-31-2008, 08:03 PM

https://www.pentaxforums.com/forums/pentax-slr-lens-discussion/28223-tamron-1...e-use-one.html

It's the fact that several samples until good is accepted with Tamron and Sigma, while we expect Pentax to be perfect on a lens that covers a wider range, is sealed to go with our sealed body and offers SDM (I loved USM, even if in the end i had none left due to budget)

It's the 16 vs 17 or 18 that is really enticing to me.

If worse comes to worse, i can shoot what i need to shoot with the 40/2.8 a KA 28/2.8 from Vivitar and the kit lens if i end up sending in my new lens (16-50) (you may notice how tempting the lens is despite knowing people keep sending theirs in/returning for another)

Good luck with your 16-50, I'd send it in to Pentax if they weren't so cruel to ask for the body too, but what's 5 days w/o, right?

Daniel

(Go and watch me change my mind 5 more times on the other thread ;P)

Pentaro · 06-05-2008, 09:02 PM

Just bought *16-50 from Amazon warehouse deal. The lens seems fine to my novice eyes, but I would love to know what you guys think.

Focus chart at 16mm:

Focus chart at 50mm:

Brick wall test [16mm F2.8 ISO100] -- asymmetric distortion, but maybe the floor wasn't horizontal:

Four corners and the center of the picture above [100% crop] -- top-left corner is soft:

Random shots (which sites host full-size jpg?):

How do you test for infinity?

Last edited by Pentaro; 06-05-2008 at 09:09 PM.

PentaxPoke · 06-05-2008, 09:43 PM

Not enough info to vote, but it sure looks better than mine did. Most of the images mine took were soft on the right. Oddly enough, I noticed it more when the lens was stopped down a bit (f3.5). I would recommend you take a pic of the brick wall outside in good sun also just to make sure.

I don't see any softness in your outdoor pics, but they are not posted at full res.

Zewrak · 06-06-2008, 02:46 AM

What do you think yourself? Seriously, you paid a bunch of dollars, do you think it performs as you expect for that cash? If so, it is good. If you can't notice anything wrong with it, its good.

roentarre · 06-06-2008, 03:28 AM

I would keep it. It seems like a good copy.

gawan · 06-06-2008, 05:00 AM

I second Zewrak and roentarre

It seems a decent copy, this lens is a tricky beast in the wide open mode, I have noticed that mine will sometime shoot just excellent and occasionally it seem to be a poor performer, but most of the time poor results are just consequences of poor conditions. 16-50 is inevitably a compromised lens compared to primes, but all-in-all this lens can be a very versatile and sharp performer.

I think that even the best copies of this lens are little soft wide open when shooting near by objects.

My advice is you a take a lot normal pictures not trying to test and see if you are happy with the result.

filorp · 06-06-2008, 04:44 PM

I think its definitely goooood one, i see slight vignetting at the very corners (bricks) and nothig else suspicious - i just discovered decenterig and terrible distortion in my 16-50 after 1 month of using it, and i'm going to send it to the service... It's too bad i didnt spot the foults just after i bought it...

ksignorini · 06-09-2008, 08:54 PM

My DA* 16-50 won't lock focus anymore. What I mean is, I aim at something, press the shutter release and _sometimes_ it flashes the red box in the middle of the focusing screen but doesn't beep. It simply flashes the box and does nothing else...exactly what you would expect in manual focus mode...except it's not in manual focus. When this happens I cannot depress the shutter release all the way and the shot is not taken (obviously).

If I adjust focus by hand and press the shutter again, it _somtimes_ moves the focus motor and refocuses fine.

Other times, it locks focus right away, beeps, and I can depress the shutter release all the way.

Any ideas? Am I just mis-remembering it working differently in the past?

thear · 06-09-2008, 09:07 PM

It appears you have the same auto focus failure problem as me. I sent my DA* 16-50mm for repairs, Pentax Service Center will be sending a new one out.

ksignorini · 06-09-2008, 09:09 PM

OK. At least I'm not imagining this.

This will be the 4th piece of Pentax gear I've sent for repair in the last year. It's getting tired. Come on Pentax...come on.

Thanks.

Wheatfield · 06-09-2008, 09:30 PM

Originally posted by ksignorini

OK. At least I'm not imagining this.

This will be the 4th piece of Pentax gear I've sent for repair in the last year. It's getting tired. Come on Pentax...come on.

Thanks.

What other gear have you had problems with, and what were the problems?

Thanks

Lance B · 06-09-2008, 10:07 PM

This also happened to me...once.

What I did was to remove the lens and then turn the AF screw drive of the camera a small amount. For some reason, the fact that it didn't line up with the screw drive of the lens meant that it didn't interface with the lens *even though it is an SDM and is using the SMD focus motor in the lens itself*. I have no idea why it worked, but it did and I haven't had an issue since.

roentarre · 06-10-2008, 01:08 AM

It happens to my copy a few times. Still, it functions well most of the time.

View Poll Results: Is this DA*16-50mm good or bad?
Keep it -- it's good.	23	88.46%
Return it or send it in for repair.	3	11.54%
Voters: 26. You may not vote on this poll

06-05-2008, 09:02 PM	#724
Pentaro New Member Join Date: Apr 2008 Location: Washington, DC Posts: 21	*Is this DA16-50mm good or bad?** Just bought 16-50 from Amazon warehouse deal. The lens seems fine to my novice eyes, but I would love to know what you guys think. Focus chart at 16mm: Focus chart at 50mm: Brick wall test [16mm F2.8 ISO100] -- asymmetric distortion, but maybe the floor wasn't horizontal: Four corners and the center of the picture above [100% crop] -- top-left corner is soft: Random shots (which sites host full-size jpg?): How do you test for infinity? Last edited by Pentaro; 06-05-2008 at 09:09 PM.*

06-09-2008, 08:54 PM	#730
ksignorini Forum Member Join Date: Apr 2008 Location: Edmonton, AB Posts: 70	16-50 won't lock focus? My DA* 16-50 won't lock focus anymore. What I mean is, I aim at something, press the shutter release and _sometimes_ it flashes the red box in the middle of the focusing screen but doesn't beep. It simply flashes the box and does nothing else...exactly what you would expect in manual focus mode...except it's not in manual focus. When this happens I cannot depress the shutter release all the way and the shot is not taken (obviously). If I adjust focus by hand and press the shutter again, it _somtimes_ moves the focus motor and refocuses fine. Other times, it locks focus right away, beeps, and I can depress the shutter release all the way. Any ideas? Am I just mis-remembering it working differently in the past?

06-09-2008, 09:07 PM	#731
thear Forum Member Join Date: Jul 2007 Posts: 83	It appears you have the same auto focus failure problem as me. I sent my DA* 16-50mm for repairs, Pentax Service Center will be sending a new one out. Last edited by thear; 06-09-2008 at 09:14 PM.

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05-31-2008, 07:39 PM	#721
morfic Veteran Member Join Date: Feb 2008 Location: San Antonio, TX Photos: Gallery Posts: 428	It's threads like these that make me s**t my pants when i go browse for 16-50 in stock, i wouldn't mind the price for what i should be getting, i just don't want to be another statistic by picking up my first bad Pentax lens. Hey! did you just remove the 16-50 from your signature? ;P Either way, i will have to have a really close look at my non-pentax 2.8 zoom thread and hopefully whatever i will decide is going to work for me in the end.....i just wish these threads (and the associated problems) didn't exist

05-31-2008, 07:52 PM	#722
PentaxPoke Veteran Member Join Date: Jan 2008 Location: Oklahoma Posts: 1,411	You are amazingly observant! Yes I did remove it. Also, your non Pentax 2.8 thread is very timely. Oh, and the first sentence of your post above, is exactly the way I felt. Unfortunately, I ended up a statistic. I do like my 50-135 though.

05-31-2008, 08:03 PM	#723
morfic Veteran Member Join Date: Feb 2008 Location: San Antonio, TX Photos: Gallery Posts: 428	https://www.pentaxforums.com/forums/pentax-slr-lens-discussion/28223-tamron-1...e-use-one.html It's the fact that several samples until good is accepted with Tamron and Sigma, while we expect Pentax to be perfect on a lens that covers a wider range, is sealed to go with our sealed body and offers SDM (I loved USM, even if in the end i had none left due to budget) It's the 16 vs 17 or 18 that is really enticing to me. If worse comes to worse, i can shoot what i need to shoot with the 40/2.8 a KA 28/2.8 from Vivitar and the kit lens if i end up sending in my new lens (16-50) (you may notice how tempting the lens is despite knowing people keep sending theirs in/returning for another) Good luck with your 16-50, I'd send it in to Pentax if they weren't so cruel to ask for the body too, but what's 5 days w/o, right? Daniel (Go and watch me change my mind 5 more times on the other thread ;P)

06-05-2008, 09:43 PM	#725
PentaxPoke Veteran Member Join Date: Jan 2008 Location: Oklahoma Posts: 1,411	Not enough info to vote, but it sure looks better than mine did. Most of the images mine took were soft on the right. Oddly enough, I noticed it more when the lens was stopped down a bit (f3.5). I would recommend you take a pic of the brick wall outside in good sun also just to make sure. I don't see any softness in your outdoor pics, but they are not posted at full res.

06-06-2008, 02:46 AM	#726
Zewrak Veteran Member Join Date: Mar 2008 Location: Nowhere, Sweden Photos: Gallery Posts: 654	What do you think yourself? Seriously, you paid a bunch of dollars, do you think it performs as you expect for that cash? If so, it is good. If you can't notice anything wrong with it, its good.

06-06-2008, 03:28 AM	#727
roentarre Veteran Member Join Date: Oct 2006 Location: Melbourne, Australia Posts: 11,783	I would keep it. It seems like a good copy.

06-06-2008, 05:00 AM	#728
gawan Veteran Member Join Date: Jul 2007 Location: Helsinki Photos: Gallery Posts: 5,400	I second Zewrak and roentarre It seems a decent copy, this lens is a tricky beast in the wide open mode, I have noticed that mine will sometime shoot just excellent and occasionally it seem to be a poor performer, but most of the time poor results are just consequences of poor conditions. 16-50 is inevitably a compromised lens compared to primes, but all-in-all this lens can be a very versatile and sharp performer. I think that even the best copies of this lens are little soft wide open when shooting near by objects. My advice is you a take a lot normal pictures not trying to test and see if you are happy with the result.

06-06-2008, 04:44 PM	#729
filorp Veteran Member Join Date: Jun 2008 Location: Aberdeen Scotland Photos: Gallery \| Albums Posts: 398	I think its definitely goooood one, i see slight vignetting at the very corners (bricks) and nothig else suspicious - i just discovered decenterig and terrible distortion in my 16-50 after 1 month of using it, and i'm going to send it to the service... It's too bad i didnt spot the foults just after i bought it...

06-09-2008, 09:09 PM	#732
ksignorini Forum Member Join Date: Apr 2008 Location: Edmonton, AB Posts: 70	OK. At least I'm not imagining this. This will be the 4th piece of Pentax gear I've sent for repair in the last year. It's getting tired. Come on Pentax...come on. Thanks.

06-09-2008, 09:30 PM	#733
Wheatfield Moderator Join Date: Apr 2008 Location: The wheatfields of Canada Posts: 15,986	Originally posted by ksignorini OK. At least I'm not imagining this. This will be the 4th piece of Pentax gear I've sent for repair in the last year. It's getting tired. Come on Pentax...come on. Thanks. What other gear have you had problems with, and what were the problems? Thanks

06-09-2008, 10:07 PM	#734
Lance B Veteran Member Join Date: Nov 2006 Location: Sydney, Australia Photos: Gallery Posts: 593	This also happened to me...once. What I did was to remove the lens and then turn the AF screw drive of the camera a small amount. For some reason, the fact that it didn't line up with the screw drive of the lens meant that it didn't interface with the lens even though it is an SDM and is using the SMD focus motor in the lens itself. I have no idea why it worked, but it did and I haven't had an issue since.

06-10-2008, 01:08 AM	#735
roentarre Veteran Member Join Date: Oct 2006 Location: Melbourne, Australia Posts: 11,783	It happens to my copy a few times. Still, it functions well most of the time.