[Rondec]

Either Kenspo or Asahi man said that the big thing that Pentax did with the DFA zooms that Tamron is making i have tighter QC on the lenses than what Tamron normally does.

My impression is that otherwise the lenses are exactly the same except for the removal of VC and the question of whether the coatings are Tamron's or Pentax's. The lens motors are certainly not traditional SDM motors, as they are quite a bit faster than lenses like the DA *16-50 and DA *50-135.

[JeffB]

I was thinking that perhaps the "VC" components could still be inside the Pentax branded lenses and possibly just disabled via firmware. But all the Tamron units are slightly heavier (~50g) so I'm guessing some internal components are not included in the Pentax units. Most likely that is the VC hardware. So I guess there's no chance of a firmware hack to enable OIS / VC in the Pentax branded units.

---------- Post added 11-09-16 at 08:43 AM ----------

If you still don't believe Tamron actually manufacturers stuff

TAMRON | Introduction to production sites

[audiobomber]

It would be easy enough to tell if there are Pentax coatings or not. Just get a Tamron 24-70mm and compare the coatings to the Pentax version. If the external element is the same colour, they are the same coatings. I recall someone on DPR posting photos of the Tamron and Pentax 18-250mm lenses, and the elements were clearly different colours. I suspect you would see the same with the D FA lenses vs. Tamron. IMO, coatings and barrels are different, the rest is probably the same. Quality control differences also makes sense (i.e. more testing on Pentax branded lenses).

[Mattox]

All I can say is that the 24-70 pentax is brilliant. Far better than any other modern Pentax lens that I have used. That is, in landscape photography, tripod, live view and all the rest.

[bdery]

So I guess there's no chance of a firmware hack to enable OIS / VC in the Pentax branded units.

The camera wouldn't know what to do with the niformation anyway.

If the external element is the same colour, they are the same coatings.

That's by no means a suficient test. If they're different, fine it's easy, but even if they look similar, their composition cuold be vastly different.

And remember that this would only be on the front element. There are coatings on each and every surface.

[BigMackCam]

I'm as interested as everyone else to know how similar the Pentax and Tamron versions are, and whether Pentax has any involvement in their manufacture. But, when all's said and done, it doesn't matter one bit - especially since the Tamron version won't be available in Pentax mount. The Pentax version is what we have, and it's clearly an excellent lens - that's all that really matters. Interesting to speculate, though. I wonder if we'll ever find out for sure?

[Digitalis]

Undoubtedly? Do you have any proof for this, then?

For the love of god, It's a matter of public record: Look it up, i'm not going to help you if you can't help yourself.

In fact, let's look inside Namioka.

good find, and some interesting information there.

Tamron has at least two factories where they grind lenses: Hirosaki factory and Namioka Factory in Niigata prefecturs. The later one is producing asferical and ultra small diameter lenses. Also the other plant is located in China - Foshan Factory.

I wasn't aware of the namioka factory...but then again I don't pay as much attention to third party lensmakers as I probably should....they are a fickle crowd.

The real question is: who is doing the coatings? You cannot rely on the appearance of the coatings on the lenses themselves, to be accurate at all you would have to disassemble the lens completely and examine the coatings on both sides of the elements under controlled conditions with a spectrometer to measure and compare the bandwidth of transmission/reflection of each element. Tedious work.

....or you could just ask Tamron.

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Last edited by Digitalis; 11-09-2016 at 07:09 PM.

[geomez]

I imagine Pentax is smart enough to avoid a PR fiasco by telling the truth when marketing the lenses as having their "HD" coatings. There are some intense and dedicated photography people out there that would dismantle the lenses and compare coatings, or adapt the lenses to work on the same camera and take test shots, looking for proof. Also I imagine lying about your product like that could cause legal problems.

[Digitalis]

adapt the lenses to work on the same camera and take test shots

I have tested a few samples of the current Tamron/Pentax 24-70mm f/2.8 lens on my optics bench, unfortunately my bench isn't designed to evaluate AR coatings. Regarding optical performance I don't have enough lenses to test to make any definitive statement on whether there is any difference between them that can safely rule out sample variation.

[walgarch]

I had a very similar question a few months back, so I messaged Roger Cicala of Lensrentals.com fame via DPR. I asked about the rear light baffle (the tamron version doesn't have one), weather sealing, optical formula and lens coatings. Keep in mind this is his speculation, but if anyone would know about this stuff it would be him:

I think it's pretty common to have some changes to the mechanicals. So better weather seals would be easy, and a rear light baffle change to reflect sensor-backfocus distances makes perfect sense. A coating change is more unusual, but certainly not hard to do.

The optical formula, though, other than coating changes, would almost certainly be identical as would the optomechanical methods of adjustment: shims, eccentric collars, etc. would adjust the same groups.

Tamron seems to be branching into a lot of rebadging, as well as specific design and manufacture to be released as another brand. Not a bad thing, they make pretty good lenses.

[audiobomber]

That's by no means a suficient test. If they're different, fine it's easy, but even if they look similar, their composition cuold be vastly different.

And remember that this would only be on the front element. There are coatings on each and every surface.

The Tamron and Pentax front and rear elements were vastly different, IIRC, one reflected blue, the other green.

[Kunzite]

For the love of god, It's a matter of public record: Look it up, i'm not going to help you if you can't help yourself.

I'm afraid this is just a rude way of not admitting you've made it up.

The source for the D FA* 70-200's barrel - or external barrel design, as you say - is not something one could find easily.

[Digitalis]

I'm afraid this is just a rude way of not admitting you've made it up.

And this is a way of saying you're content with standing in the fog of your inability to do your own research, placing the burden of proof on someone else shoulders instead of pulling the line yourself.

From Tamrons coprorate history:
1985: Tamron Fine-Giken Co. Ltd. is established and produces high precision molding components.
1986: The molding technology production facilities in Owani-machi, prefecture Aomori are completed. Here key high-precision plastic and metal components are manufactured.

It stands to reason that Tamron still has these facilities, considering that the design cues for their current generation of lenses such as the 15-30mm lens barrel is evident on the Pentax the 24-70mm, 15-30mm as well as the 70-200mm is evident in the current pentax zoom lens line up.

[Kunzite]

The burden of proof is on that who makes the claim. Always. By the way, that's you.

And for all your insults, you're awfully confused:
- the D FA 15-30 and D FA 15-30 are rebadged Tamron lenses, made by Tamron in their Japan factory, with Pentax customization. They're not D FA* lenses.
- the D FA* 70-200 f/2.8 is unrelated to any Tamron lens; it's a Pentax design, made by Pentax in their Vietnam factory. There's no design cue on it's barrel that it might be related to any Tamron - because it isn't. By the way, it's the only D FA* so far.
Your claim was about Pentax "getting the designs for the external barrels for the newer DFA* lenses" from Tamron.

[Digitalis]

your claim was about Pentax "getting the designs for the external barrels for the newer DFA* lenses" from Tamron.

You don't see anything in common in the physical design of the barrels on these two lenses? absolutely nothing at all?