[aldo taddia]

Health to All. Why do I read about so many new Pentax lenses that have alignment problems or not perfect definition and that are then returned or replaced? I have been taking photographs for 50 years, I have had dozens and dozens of optics and I have never encountered this problem. Have I been lucky, or do I have little ability to recognize lens defects? Thanks to those who can give me an answer.

[Cerebum]

Health to All. Why do I read about so many new Pentax lenses that have alignment problems or not perfect definition and that are then returned or replaced? I have been taking photographs for 50 years, I have had dozens and dozens of optics and I have never encountered this problem. Have I been lucky, or do I have little ability to recognize lens defects? Thanks to those who can give me an answer.

I think this is much like reviews. People don't write unless they have an issue so the majority of text posts are issues, whereas the majority of users are happy. There are always going to be donkeys but I like to believe they are pretty rare

[DamienW]

I read that about a lot of lenses. Never had an impression that it was more with one make than another (except Samyang, when I was looking into their wide lenses for astro work...but that may have just been because I was reading up on them a lot).

[kypfer]

Health to All. Why do I read about so many new Pentax lenses that have alignment problems or not perfect definition and that are then returned or replaced? I have been taking photographs for 50 years, I have had dozens and dozens of optics and I have never encountered this problem. Have I been lucky, or do I have little ability to recognize lens defects? Thanks to those who can give me an answer.

More or less what Cerebum wrote!
It's a combination of happy users not bothering to give any feedback at all and the wide availability of "social media" and on-line reviews to report problems, perceived or otherwise.
One dissatisfied customer posting in five different forums or similar can easily be translated as five faulty units.
Multiply these by the "I read that somewhere else" crowd and you've got five active threads all based on one allegedly faulty item!
The interweb is a wondrous thing

[i_trax]

Users are getting more and more paranoid about perfections.
Pixel peepers are becoming kind of norm rather than exceptions partially due to better & better & higher resolution monitors.

I never be like that , if lens is not perfectly sharp in every corner , that actually adds into the lens unique character and I am happy with that.
We should just enjoy photography and not becoming the slaves of digital pureness.

[BigMackCam]

Users are getting more and more paranoid about perfections.
Pixel peepers are becoming kind of norm rather than exceptions partially due to better & better & higher resolution monitors.

^^^ This.

A few years back, I noticed during testing and AF fine adjustment that a lens I'd bought wasn't perfectly centered and, as a result, was a little softer in one quadrant, especially in the corner, at wider aperture settings. I spoke to a reputable lens technician about servicing it, and he joked that such problems never existed in the days of 35mm film, as you just wouldn't notice such a small issue. Even in the earlier days of digital, the lower-resolution sensors weren't capable of resolving the minor issues we now see all too easily with 24MP, 36MP and even-higher-resolution sensors.

The simple fact is, very few lenses are perfectly aligned - even those we think are. Roger Cicala at LensRentals has plenty to say on this, and of all people, he should know. If you look hard enough for problems, the chances are you'll find them on most lenses. The problem is, we've become used to examining and editing our images at 1:1 reproduction on 24" high-definition monitors whilst sitting 30cm away, and in those conditions some of us will notice even the tiniest optical deficiencies. I don't worry unless I can see them when a photo is scaled to fit my 24" BenQ QHD monitor and viewed at normal working distance...

[jersey]

^^^^
This.

People care too much. Just enjoy your lens. My 55-300 has issues with big distances (1000+ meters) and resolution. It is most likely lens fault as lots of people don't report it. I have cared, thought about replacing lens etc but then I printed such "fault" image in wall image size (60x40 cm), put in on the wall and looked from few steps away. And stopped to care. Big, high res monitors killed the joy of just watching at photos and enjoying content. We "need" that every pixel is perfect.

[aldo taddia]

Thank you for your comforting words! I thought I was the one who had always been lucky to buy my lenses.
I was worried about a possible new purchase of the 21mm f.2.4, having read the bad reviews in a review of this lens, then corrected in excellent, having replaced the defective copy with a fully functional one.
It seemed that one in two copies was with badly centered lenses or with other defects and that you had to check it and then have to send it back .

[Michail_P]

I have been very lucky too. My manual lenses are quite good, though older than me.. My kit lens is fantastic too...

[AfterPentax Mark II]

^^^ This.

A few years back, I noticed during testing and AF fine adjustment that a lens I'd bought wasn't perfectly centered and, as a result, was a little softer in one quadrant, especially in the corner, at wider aperture settings. I spoke to a reputable lens technician about servicing it, and he joked that such problems never existed in the days of 35mm film, as you just wouldn't notice such a small issue. Even in the earlier days of digital, the lower-resolution sensors weren't capable of resolving the minor issues we now see all too easily with 24MP, 36MP and even-higher-resolution sensors.

The simple fact is, very few lenses are perfectly aligned - even those we think are. Roger Cicala at LensRentals has plenty to say on this, and of all people, he should know. If you look hard enough for problems, the chances are you'll find them on most lenses. The problem is, we've become used to examining and editing our images at 1:1 reproduction on 24" high-definition monitors whilst sitting 30cm away, and in those conditions some of us will notice even the tiniest optical deficiencies. I don't worry unless I can see them when a photo is scaled to fit my 24" BenQ QHD monitor and viewed at normal working distance...

Your reputable technician is absolutely right. Sometimes it is just that you do not like the lens you are using. Or your expectations are too high, because you got influenced by the manufacturers description, who most of the time think they produce miracles instead of lenses and camera's to stay on the subject of this forum. And it is especially with my K-3 II that I noticed such things for the first time. I got to that camera from my Samsung GX-10, so quite a leap upwards. Between the two there is a gap of eleven years. But most of the time I think I am at fault, not the gear. And one lens performs better on one camera than on the other. I guess that has a bit to do with matching the quality of the lens with the camera. The DA* 55mm looks brilliant on my K-3 II, but not so on the GX-10.

[BigMackCam]

Thank you for your comforting words! I thought I was the one who had always been lucky to buy my lenses.
I was worried about a possible new purchase of the 21mm f.2.4, having read the bad reviews in a review of this lens, then corrected in excellent, having replaced the defective copy with a fully functional one.
It seemed that one in two copies was with badly centered lenses or with other defects and that you had to check it and then have to send it back .

You have to be wary when reading negative reports of lenses, and careful when drawing conclusions from them. Just because someone had what they consider to be a defective lens, doesn't mean you or I would have considered it so. Some folks have impossibly high standards. Then, just because they had a supposedly defective lens and the replacement was better, doesn't mean that every one in two of those lenses is bad. It just means that they were unlucky with the first, and luckier with the second. Who knows, maybe that second copy would also be deemed defective by someone with yet higher, even-more-unrealistic standards... and maybe I'd consider both copies to be perfectly acceptable. There's quite a degree of subjectivity in it, unless it's a really obvious problem, of course.

Obvious de-centering - where you can clearly see a difference in symmetrical resolution when viewing a photo at typical dimensions and viewing distances - is a valid reason for concluding it's defective. So, too, is the inability to adjust it for accurate focusing within the camera's AF fine adjustment limits (assuming the camera isn't at fault). It's possible with any lens - even high-end models, from any manufacturer - to have a few examples slip through quality control exhibiting these issues. We seem to feel $2,000 is a lot to spend on a complex, high-precision optical device, and we expect it to be perfect, yet we think nothing of a $50,000 - $100,000 luxury car requiring mechanical adjustment and servicing even soon after delivery. Sometimes, our ideas are out of whack to a far greater extent than our lenses

[ehrwien]

If you look hard enough for problems, the chances are you'll find them on most lenses.

To quote from The Matrix: "Ignorance is bliss." I have used a flashlight to look inside a lens once, and I'm afraid of doing it to any other lens I have. Meanwhile they all produce great images where I wouldn't be able to tell the difference to ones produced with the same lenses, but in pristine condition. How I learned to stop worrying and love the images

[BigMackCam]

I have used a flashlight to look inside a lens once, and I'm afraid of doing it to any other lens I have. Meanwhile they all produce great images where I wouldn't be able to tell the difference to ones produced with the same lenses, but in pristine condition. How I learned to stop worrying and love the images

LOL

The "flashlight test" requires guts, but over time I've learned to accept and understand what I see. I only do it with older, used and/or vintage lenses, and only then if a casual look through one in daylight leaves me suspicious. I don't care about some dust and the odd bit of debris, nor indeed inclusions in the glass. I only want to see if there's fungus, haze, balsam separation etc. Very few lenses look good with a flashlight shone through them, and vintage ones typically look awful

[ffking]

I think cost the relative cost and advertising copy have both been ramped up in recent years, so people are less tolerant of anything other that the perfection than they parted with considerable amounts of money for - and have to say that some of my favourite pics were taken on kit lenses that were simply adequate to the task and I didn't expect too much of.

[robgski]

Don't let "perfect" be the enemy of "good". If you haven't noticed any issues, there probably are not any issues. Life is too short to worry about nonsense or engage in pixel peeping, less yapping, more snapping, go out and use your gear, then post the results here.