Are de-kitted lenses more prone to sample variation?

assaft wrote:

Wasabi Bob wrote:

Yes, I do ... I've seen the manufacturing process from start to finish.

1. The final testing is automated - you don't have humans deciding what is "good" or "bad". Unless you can assign human qualities to an automated testing apparatus, I'd say that they've removed the human variable from the manufacturing process. It's automated to the extent that you typically have only 1 - 2 persons in charge of the entire line.

2. As with any product, there are mechanical (and other) tolerances. Granted, the design tolerances will be higher on more expensive lens but the variation is not going to be that great so as to deem a lens unacceptable. Any lens that does not pass the test is ejected off the line.

3. As some one else stated (which I totally agree with) much of the negative comments are the result of the customer's expectations. Whether a lens has a metal or plastic mount, has no bearing in the optical quality. With Panasonic's lens the mount it is largely decided by the target weight of the final product.

A "kit" lens is often a middle of the road (in terms of specs) lens that they've decided to produce in much larger quantities so the cost decreases. Cheaper is not necessarily lesser quality. A good example is their 12-32 lens. It's small, relatively inexpensive and quite sharp. It's not the fastest lens in terms of aperture, but it serves most people very nicely as a starter lens.

I'm not doubting what you've seen or being told in the Panasonic's factory that you say you visited. But I think it isn't enough to explain the situation.

For example, there was a peak in the number of reports on problems with lenses from the first batch of the P 42.5/f1.7, which were sold for 100$. I don't see a good reason to attribute all of that to packaging and shipment. Probably there's nothing unique to the way this batch of this particular lens is packaged or shipped compared to other batches/lenses. In addition, if what you say - about the manufacturing and testing process being completely automatic - is correct, I don't understand how so many problems weren't caught in the factory. It's a failure of two separate components (the assembling one and the testing one).

In addition, you say that there is a certain degree of tolerance for imperfection but you've been told that it is fairly low and should be a non-issue in practice. I'm not sure about that. We can't really know what their degree of tolerance is and whether it is indeed as low as they make it sound. During the last few years I've seen several posts by users who clearly demonstrated de-centered lenses but when their lenses were sent to Panasonic for repair under warranty they got an answer that the lens performance is within the vendor normal range. Note that only a small number of users actually take the trouble to test their lenses so the presence of such reports is likely to indicate a problem of a wider scope.

By the way, I don't want my posts in this thread to sound as if Panasonic is the only vendor with such problems. It is no secret that sample variation is common in lenses from almost all manufacturers.

Pikme wrote:

Wasabi Bob wrote:

I really fail to see the humor in your response. So much of the info shared in such discussion begins as someones "opinion". It magically becomes fact and people start forming conclusions on assumptions. I've been to where the lens are manufactured and have a close working relation with their service network, globally. I'm not pulling rabbits out of a hat when I made those statements.

There is no value to the ridiculous theory that a well known company, in this case the largest manufacturer of aspherical lens in the world, intentionally sells inferior copies of a lens. People who are new to digital photography look to these forums for guidance. Any info should be factual and accurate.

Pikme wrote:

Wasabi Bob wrote:

Assaft

I've had some professional interaction with Panasonic as well as having the opportunity to visit their facilities in Japan. There is no such thing as a "bad copy" of a lens. When the lens leaves the factory, all are equal. The assembly is all automated, so they've removed the human factor which could introduce variations. If you see any difference, it's likely due to shipping related damage. When I see such comments, it almost sounds like some people believe that they are running some sort of lens counterfeiting operation.

Are you interested in ocean front property for sale in Arizona? I can get you a real bargain!

Sorry you didn't like my humor, but you are either incredibly naive or blinded from reality for some other reason. I'm not knocking Panasonic, although I am disappointed in the obvious lessening of QA for both Panasonic and Olympus since the switch from 4/3 to m4/3. Still, I don't believe either company is any worse than other camera company today.

It is just not possible (and is itself humorous to state) to remove all variability and human factor from any type of manufacturing. Besides, camera companies also buy parts, lens housings, optical components, contract manufactured complete lenses, etc. That is particularly true for cheaper or kit lenses, which are often contracted from third party manufacturers, including sometimes the entire design and development of the lens.

Do you really believe there is no variability or human factor involved in the manufacture of the 100-400 lens? Or that Panasonic spends as much time and effort assuring acceptable quality for every copy of the 12-32 lens as they do the 100-400 lens?

The 42.5 f1.7 or the 25mm? I don't remember complaints about the former...

Anyway, if they really told Wasabi that they meticulously test every lens off the line for decentering, then they were just straight up blowing smoke up his... Or their test only checks for the kind of decentering that would happen if you take a hammer to the lens.