[GeneV]

As said repeatedly in many threads here, there may be a number of 16-50s that have clear decentering and other QC issues, but these problems were largely sorted out in the second wave of production of the lens. Saying that there are a ton of bad copies is a gross exaggeration.

Whether or not you would buy it, the 16-50 is an excellent lens in every way, and I (as well as many other users) have a plethora of examples where this lens outshines any other in its focal range.

I don't doubt that there are many more excellent DA 16-50 copies out there than bad, but the threads on the bad ones seem endless and ongoing. We would be somewhat remiss in not accepting the possibility of a bad copy. A bad lens is not usually my first conclusion, but the Kangaroo photo has no area in it which is critically sharp, and that could very well be a bad lens. It is a bit of a coincidence that the particular DA* which is the subject of the OP's complaint is in fact one about which there has been a great deal of controversy.

[Marc Sabatella]

I looked at the bike pics and I can see that the background is in focus rather than the biker himself.

Such cases are essentially *never* lens defects, or camera defects. They are simply a matter of the camera having chosen to focus on the background rather than whatever was intended. Cameras are not mindreaders.

Camera/lens defects show up as differences in focus of *centimeters*, not *meters*.

[GeneV]

Camera/lens defects show up as differences in focus of *centimeters*, not *meters*.

True. Which is why the Kangaroo photo is more indicative of a lens or camera problem--unless it is a crop that is focused outside the area that was retained. Everything in that photo is just a little off.

The lens performance in the bike photos looks fine. It is sharp at the point of focus. The bike is also taken with a different lens from the kangaroo as the focal length is 70mm, whereas the Kangaroo says it was taken with the 16-50.

[Marc Sabatella]

Could be. I couldn't find any of his photo in the 10 seconds or so I thought it was worth to try. If he'd post pictures here in these threads themselves, I'd look.

[Ash]

I don't doubt that there are many more excellent DA 16-50 copies out there than bad, but the threads on the bad ones seem endless and ongoing. We would be somewhat remiss in not accepting the possibility of a bad copy. A bad lens is not usually my first conclusion, but the Kangaroo photo has no area in it which is critically sharp, and that could very well be a bad lens. It is a bit of a coincidence that the particular DA* which is the subject of the OP's complaint is in fact one about which there has been a great deal of controversy.

BF/FF should always be addressed before labelling a lens as 'bad'.

Fearing to pick up a 'bad' copy because of the numerous threads posted here raising such complaints will just mean you'll never get one. As mentioned, buying one new now is no longer a lottery for getting a 'good' one.

Also put it into perspective - there are countless satisfied 16-50 owners who never post how great their lens is on the forum, but have an unhappy user, and you'll see no end to the threads of criticism posted. Perhaps you can check out the forum's lens review database and see how *some* of the users there felt about this lens. Many of the pros on this forum have used this lens in spectacular fashion.

So all I'm saying is despite the bad wrap this lens has received, the issue is not about whether this lens is 'bad' or not - it is a stellar lens, just whether it suffers from QC issues, which has largely already been addressed for some time now.

[Miserere]

I used to write one poem every day, and it sucked. But now that I write 10 poems a day I feel I'm an expert. I must be, cos that's like 70 poems a week.

Last week I bought a new pen, and now my poems suck again. It's not me, because I write 10 poems each day. It's the pen.

Ranters, please read this article. I would then advise you to send cameras and lenses to Pentax to have them callibrated together.

DA* lenses with SDM do not focus significantly faster, if at all. They're just quieter.

The faster your lens (wider aperture) the better its focusing needs to be callibrated. Maybe some K20D's, with AF adjustment for individual lenses, would be a better choice for your needs.

[Ben_Edict]

I used to write one poem every day, and it sucked. But now that I write 10 poems a day I feel I'm an expert. I must be, cos that's like 70 poems a week.

Last week I bought a new pen, and now my poems suck again. It's not me, because I write 10 poems each day. It's the pen.

Excellent!

Ben

[cwood]

Photo of bike:

- Photo is taken at F9.5 ISO 1600 1/3000 sec
- Photo is taken in "Action" mode
- Photo is poorly framed with terrible background
- Photo is underexposed
- Photo has strange hues - good guess would be in-camera jpg processing with odd saturation setting
- lens produces photos that are sharp sometimes in some places

Conclusion:
Lens is fine - photographer is broken. Send in for repair immediately.

In all seriousness though (and because this is a Pentax forum people might think I'm just being an ass but I'm not...) my best advice to the photographer is to get a used Canon 30D and a used 70-200/4 and sell all the Pentax gear. Pentax requires a lot of practice, skill and a variety of techniques to successfully capture action photos. The Canon setup is much more point and shoot friendly and will produce more keepers. A photojournalist just can't get away with snapping photos on a K200 in "Action" mode and hope to get the same rate of success.

Perhaps K-7 has achieved that level but it's only been on the market a few days now so I think its safe to say the jury is still out on just how fast it is.

[babelphotos]

Mmmmhhh!!
Well let me put my two cents on that one. It will take a miracle for me to buy another Pentax lens...why?? OK

1 The 16-50 is complete doo doo. Just check the list of issues in this forum...well i have them.

2 The 50-135 died on me 7 months after purchase. Reason...one of the small plastic gears inside broke and they had to change the entire autofocus motor. Result, i lost the lens for 4 months.

3 The 200 f2.8 is soooooooo sllllloooooooowwwww basically cant work with it.

I have the 50-500 sigma lens....WOW works like a charm
another sigma is the 120-400 2.8. This lens is expensve but beats the crap out of every lens i use on the Canon.

So yes Pentax could have issues with their lenses...i know i have.

[GLXLR]

Photo of bike:

- Photo is taken at F9.5 ISO 1600 1/3000 sec
- Photo is taken in "Action" mode
- Photo is poorly framed with terrible background
- Photo is underexposed
- Photo has strange hues - good guess would be in-camera jpg processing with odd saturation setting
- lens produces photos that are sharp sometimes in some places

Conclusion:
Lens is fine - photographer is broken. Send in for repair immediately.

In all seriousness though (and because this is a Pentax forum people might think I'm just being an ass but I'm not...) my best advice to the photographer is to get a used Canon 30D and a used 70-200/4 and sell all the Pentax gear. Pentax requires a lot of practice, skill and a variety of techniques to successfully capture action photos. The Canon setup is much more point and shoot friendly and will produce more keepers. A photojournalist just can't get away with snapping photos on a K200 in "Action" mode and hope to get the same rate of success.

Perhaps K-7 has achieved that level but it's only been on the market a few days now so I think its safe to say the jury is still out on just how fast it is.

What a "friendly" introduction...-_-

Although it's funny how you said you were a pro. A lot of the users here are much more experienced than you. Try to be a LITTLE more modest next time ehh? ;-D (I am no pro by any means)

K200D is more friendly IMO than the 30D. Trust me, I switched from the 30D to the GX-10 (or I accidently bought a 30D and returned it the second it got on my doorstep )

[JonPB]

From looking at the bike images, I can't judge whether one lens is better than another. There is a lighting difference, which could be due to white balance settings or to lens coloration, or to the hour between photos. There's also a difference in sharpness of the subject, but in one picture the subject is going up (and would therefore be moving slower) and in the other the subject is going down (and therefore faster). What about the Sigma-lens image do you find superior to the Pentax-lens image? If you could post a 100% crop of the comparison, that would be great.

My best guess is that the DA* handles differently from the Sigma you're used to. Not that it is an inferior lens, just that it behaves differently--and so the photographer's technique needs to compensate for it. With every lens I've had, there are ins and outs that I need to learn before I can appreciate all of its qualities. Then again, I've never used a * lens.

I'll reiterate what others have said: the more specifics you can provide about the problems you're experiencing, the more likely we'll be able to help.

Do the DA* lenses have any problems with static objects? Say, if you focus on an object that's a meter or two away from your computer right now ... do you find the Sigma to be superior? One of my typical tests with a lens is to open a book, focus on a certain line of text, and then compare results (between apertures, between lenses, whatever).

Cheers.

[Pentaxor]

Photo of bike:

- Photo is taken at F9.5 ISO 1600 1/3000 sec
- Photo is taken in "Action" mode
- Photo is poorly framed with terrible background
- Photo is underexposed
- Photo has strange hues - good guess would be in-camera jpg processing with odd saturation setting
- lens produces photos that are sharp sometimes in some places

Conclusion:
Lens is fine - photographer is broken. Send in for repair immediately.

In all seriousness though (and because this is a Pentax forum people might think I'm just being an ass but I'm not...) my best advice to the photographer is to get a used Canon 30D and a used 70-200/4 and sell all the Pentax gear. Pentax requires a lot of practice, skill and a variety of techniques to successfully capture action photos. The Canon setup is much more point and shoot friendly and will produce more keepers. A photojournalist just can't get away with snapping photos on a K200 in "Action" mode and hope to get the same rate of success.

Perhaps K-7 has achieved that level but it's only been on the market a few days now so I think its safe to say the jury is still out on just how fast it is.

does this mean that the K-7 is not ideal for novice shooters?

setting aside humor, by the way I handled the K-7, it is somewhat a lil bit challenging, especially when using those tweaking features. I found the features of the Pentax system tricky at first as compared to other systems which I found to be more user-friendly. not just the system but also the lenses. I concur to this since I did some shots with the 1.2, considered to be one tricky lens by people in this forum. there is a thing such as a sweet spot in lenses. probably that's what the OP hasn't been able to figure it out. you need to work the lenses as well.

*I made this comment just in case the camera and the lens are perfectly fine. anyway, if the OP is really pissed with his DA* lenses, I'd be willing to buy both of his lenses for 500 bucks.

[cwood]

What a "friendly" introduction...-_-

Although it's funny how you said you were a pro. A lot of the users here are much more experienced than you. Try to be a LITTLE more modest next time ehh? ;-D (I am no pro by any means)

K200D is more friendly IMO than the 30D. Trust me, I switched from the 30D to the GX-10 (or I accidently bought a 30D and returned it the second it got on my doorstep )

It was a pretty light hearted post I made there. I made no claims anywhere in this thread about being "pro" so I'm not sure why you find that funny... and I said nothing that was un-modest. It is true I make my living taking photos but what difference does that make? I'm pretty sure I have never claimed that I am an expert (if I have then I apologize).

At F9.5 just about any lens will look the same
At ISO 1600 (underexposed) the K200 will have enough noise in the image that "sharp" will be almost impossible to tell.

And this thread was supposed to be a complaint by a skilled pro photographer (photo journalist) about how bad the Pentax lenses were. I'm sorry but at those setting it is impossible to rate the quality of any lens. I don't have to be a pro to know that. The MODEST thing to do would have been to ask the group of Pentax enthusiasts who hang out here (pro's, skilled enthusiasts, and beginners) what was wrong with HIS pictures when so many other people have had so much success with these fantastic lenses. There is a long thread here call "why 50-135 does not suck" and it is filled with hundreds of fantastic pictures taken with that lens. A MODEST approach by the thread starter would have produced a much more informative set of replies.

Yah I was being a little bit of an ass but it was a "true" and lighthearted post and it was an appropriate reply to the quote that started this whole thread:

"has anyone know why the da* lenses dont focus properly
I have found that cheap sigma lenses out perform the most expensive pentax lenses. I keep getting out of focus shots which never happened with sigma lenses"

followed by this:

"i take hundreds of pics every week i am a photo journalist and run 5 pentax cameras with lenses attached to them all these lenses dont come up to the mark and they should"

"I have 5 pentax cameras and just bought 2 da* lenses and they r both the same and 3 cameras are brand new. even on static objects the focus seems to vary. Has me beat this one and i take thousands of pics each month"

"I am the photojournalist. As i said yea i did pay out big bucks for 2 Da* lens. No its not me. I do know what I am doing.... My experience tells me that the lenses do not perform otherwise i would not be here. To many people rely on my pics "

[Ash]

Whatever conclusion we all come to about the * lenses, it's evident that many users (who know how to use them) have created professional photos of unrivaled quality and brilliance with them.

[Pentaxor]

I so want ranters DA* lenses right now. if he really feels that about DA* lenses in general, I would certainly be happy to have those lenses. but since they suck so much, he should give them to me free of charge. fair deal for sucky lenses, eh !