[Harald]

Please let us know as soon as possible how the new one performs. If you get good copy, there is still hope.... but if I decide to ask replacement, it maybe takes some time before I get it. I ordered this one nine, yes, nine months ago... among first ones in this country.

[2fast4you]

Ohoh...no. I hoped there are only a few bad 16-50s out there. I tought about buying a 16-50, but while reading feedbacks like this I'm thinking about the 16-45 more and more.

[Kaimarx]

The one reason i would have decided to go with zooms was the DA*s based on the expectation. As i understand it the quality control on the series is the worst in Pentax's long history...i wonder if this is a direct result of Hoya trying to flood the market with product at a cheaper cost. I would have preferred Pentax's former approach. Slowly but surely. You cant put a price on assurance.

[2fast4you]

But why is it only the 16-50?? The 50-135 showed absolutely outstanding results...

[fwbigd]

But why is it only the 16-50?? The 50-135 showed absolutely outstanding results...

I have had two DA*16-50s. The first was defective. The second is outstanding. The story that my dealer was told by the Pentax rep was that the first batch of 16-50 were hand calibrated. The second shipment of lens were computer calibrated using a laser. Don't ask me what that means.

All I know is my second copy is a world class lens!!!!

[Kaimarx]

I have had two DA*16-50s. The first was defective. The second is outstanding. The story that my dealer was told by the Pentax rep was that the first batch of 16-50 were hand calibrated. The second shipment of lens were computer calibrated using a laser. Don't ask me what that means.

All I know is my second copy is a world class lens!!!!

Well that is a little reassuring now that theres an explanation, can those of you who have the defective (suspected) copies post your serial numbers. It would go a long way to identify the affected batches for those who are yet to walk in the store and play international ping pong with Pentax over shipping defective stock. Im hoping stockists are alerted duly by all Pentax reps if this the case. Still its better to be safe than sorry.

[Maxington]

DA* 16-50 is softer at f2.8, for sure, I don't think any copies of it will be hugely sharp wide open. Its not soft at 16mm or any focal length when its at f4 or higher. It slightly exceeds the Tamron 28-75 in sharpness at f2.8, and kicks its butt at all other fstops, so its not like its actually a soft lens, but it is more expensive.

The contrast of the lens however is off the scale. If anyone is thinking of buying it, don't get all hung up over sharpness at f2.8, its a brilliant lens. It takes jaw dropping photos, I can see why some people even complain that its too contrasty, its like a overprocessed jpeg from a P&S compared to other lenses if you process them the same way.

If you want sharpness at f2.8, you might have to go to a faster prime and stop down.

[wtlwdwgn]

When I purchased my 16-50 in November, most of the online stores were out of stock so I ordered it from Pentax USA. It took a week to get it via Fedex and when I checked on the tracking, I found that it had been shipped directly from the factory in the Philippines. I have only taken about 300 images so far, but I think I got a good copy. Maybe QC is getting better with time.

[rvannatta]

DA* 16-50 is softer at f2.8, for sure, I don't think any copies of it will be hugely sharp wide open. Its not soft at 16mm or any focal length when its at f4 or higher. It slightly exceeds the Tamron 28-75 in sharpness at f2.8, and kicks its butt at all other fstops, so its not like its actually a soft lens, but it is more expensive.

The contrast of the lens however is off the scale. If anyone is thinking of buying it, don't get all hung up over sharpness at f2.8, its a brilliant lens. It takes jaw dropping photos, I can see why some people even complain that its too contrasty, its like a overprocessed jpeg from a P&S compared to other lenses if you process them the same way.

If you want sharpness at f2.8, you might have to go to a faster prime and stop down.

I believe mine in an early one with a 9012nnn serial number. My first experiences with it were quite negative, however, I resolved the going crazy focusing issue by simply changing a camera setting. Specifically, I went to center weighted focusing instead of screen average default method. It is my theory that with the wide angle, and the fact that the view finder doesn't show everything---- with the screen average focusing you are all too often focusing on things you can't see off the edge of the viewfinder.----particularly when you are at the 16mm setting.

Once I changed to center weighted focusing, my frequent grossly miss focused photos disappeared.

[jbcampbell]

I believe mine in an early one with a 9012nnn serial number. My first experiences with it were quite negative, however, I resolved the going crazy focusing issue by simply changing a camera setting. Specifically, I went to center weighted focusing instead of screen average default method. It is my theory that with the wide angle, and the fact that the view finder doesn't show everything---- with the screen average focusing you are all too often focusing on things you can't see off the edge of the viewfinder.----particularly when you are at the 16mm setting.

Once I changed to center weighted focusing, my frequent grossly miss focused photos disappeared.

Huh? Center Weighted is the metering pattern, it has nothing to do with focus at all. Do you mean you started using the center focus point?

[jbcampbell]

DA* 16-50 is softer at f2.8, for sure, I don't think any copies of it will be hugely sharp wide open. Its not soft at 16mm or any focal length when its at f4 or higher. It slightly exceeds the Tamron 28-75 in sharpness at f2.8, and kicks its butt at all other fstops, so its not like its actually a soft lens, but it is more expensive.

The contrast of the lens however is off the scale. If anyone is thinking of buying it, don't get all hung up over sharpness at f2.8, its a brilliant lens. It takes jaw dropping photos, I can see why some people even complain that its too contrasty, its like a overprocessed jpeg from a P&S compared to other lenses if you process them the same way.

If you want sharpness at f2.8, you might have to go to a faster prime and stop down.

For the price of this lens it should take usable (acceptably sharp) photos @ F2.8. If not then why spend the money? I also shoot with canon gear, I have several L series F2.8 zooms that are very sharp wide open. My point is not that Canon is better but that Pentax can & should make a comparable alternative.

[wtlwdwgn]

I believe mine in an early one with a 9012nnn serial number. My first experiences with it were quite negative, however, I resolved the going crazy focusing issue by simply changing a camera setting. Specifically, I went to center weighted focusing instead of screen average default method. It is my theory that with the wide angle, and the fact that the view finder doesn't show everything---- with the screen average focusing you are all too often focusing on things you can't see off the edge of the viewfinder.----particularly when you are at the 16mm setting.

Once I changed to center weighted focusing, my frequent grossly miss focused photos disappeared.

Thanks for this post. I learned some more about my K10D. I just changed to the center weighted focusing and wowzers, no more hunting. My lens' SN is 9015nnn. I've only had the K10D for a month and I learn something new every day.

As far as getting usable images at the widest f stop at the widest focal length, slr lens designers must be having tremendous acid reflux. Back in the 60's we never expected to get good images at the widest f stop on a prime lens let alone a zoom. The designers gave us f1.4 or f1.8 so we could see to focus in low light conditions and not to give good images. The only lenses that were guaranteed to provide sharp images at the widest f stop were Leica's rangefinder lenses because it made no sense to put an unusable f stop on a RF lens. Even then the Noctilux had noticeable vignetting at f1.0! With today's technology I think it's amazing that we are getting the images we do at f2.8 on a zoom lens.

[Maxington]

For the price of this lens it should take usable (acceptably sharp) photos @ F2.8. If not then why spend the money? I also shoot with canon gear, I have several L series F2.8 zooms that are very sharp wide open. My point is not that Canon is better but that Pentax can & should make a comparable alternative.

Didn't you read my post? It does take acceptable images at f2.8. It beats the Tamron 28-75. It just is much sharper at 5.6, like most lenses.

How much are your Canon f2.8 zooms though, the IS versions to be comparable, and L glass for weather sealing to be truly equal. A hell of a lot more than $1000 USD.

Not sure there is any market for even higher end lenses for Pentax at the moment.

[jbcampbell]

Thanks for this post. I learned some more about my K10D. I just changed to the center weighted focusing and wowzers, no more hunting. My lens' SN is 9015nnn. I've only had the K10D for a month and I learn something new every day.

As far as getting usable images at the widest f stop at the widest focal length, slr lens designers must be having tremendous acid reflux. Back in the 60's we never expected to get good images at the widest f stop on a prime lens let alone a zoom. The designers gave us f1.4 or f1.8 so we could see to focus in low light conditions and not to give good images. The only lenses that were guaranteed to provide sharp images at the widest f stop were Leica's rangefinder lenses because it made no sense to put an unusable f stop on a RF lens. Even then the Noctilux had noticeable vignetting at f1.0! With today's technology I think it's amazing that we are getting the images we do at f2.8 on a zoom lens.

I think it's safe to say that lens design & manufacturing have come a long way since the 60's. I don't expect any lens to be as sharp wide open as it is stopped down a few stops but the image should be usable. The bottom line is the 16-50 I got was either defective, the product of a bad batch or the lens has a design flaw. It's possible to design & build a 2.8 zoom that produces good image quality wide open, I own several. I am just disappointed with this particular lens, hopefully my replacement will be a better copy

[roentarre]

The contrast of the lens however is off the scale. If anyone is thinking of buying it, don't get all hung up over sharpness at f2.8, its a brilliant lens. It takes jaw dropping photos, I can see why some people even complain that its too contrasty, its like a overprocessed jpeg from a P&S compared to other lenses if you process them the same way.

With films, I always desire high contrast and strong colour like fortia films which are limited in production and costing 34 dollars per rool of film. Not sure why some people absolutely hate high contrasty images ...