[Mistral75]

(...)



Sigma 35- art


Nikon Fans 1.8G


Nikon 35mm 1.4 G


canon EF 35 ƒ1.4 USM -L


31 ltd.


(...)

May I point out that your comparison of Photozone sharpness graphs is unfair as far as corner sharpness is concerned?

- the Sigma 35mm f/1.4 DG HSM | Art, AF-S Nikkor 35mm f/1,8G and AF-S Nikkor 35mm f/1,4G were tested on a Nikon D3X, a 24x36 camera
- the Canon EF 35mm f/1.4L USM, an old lens (1998) replaced in 2015, was tested on a Canon EOS 5D Mark II, a 24x36 camera
- the smlc Pentax-FA 31mm f/1.8 Limited was tested on a Pentax K-5, an APS-C camera.

Corner sharpness...

[D1N0]

sharpness scores can only be compared between the same or similar sensors

[normhead]

I t is really hard to explain what you mean by every statement, every implied fact, every nuance, every caveat for every point you make on the internet, give us a break here. The hope is that your readers will understand the your point without having to write a 10 page essay. Once you get the gist of what is being said, the little details are un-important.

I would really like to acknowledge the effort both Sigma and Tamron made, staying with Pentax so long. They never raised pentax prices. They never said "We don't make as much money on Pentax so each lens made for Pentax should cost more." When I checked prices the Pentax price was pretty much the same as the Nikon of Canon price. They turned down a lot of profit trying to keep the mount alive. I own a Tamron AF SP 3002.8 in K-mount that internet rumour has it that only 100 were ever made. Tamron took a loss on that. They may have lost more on my copy than I paid for it. And I have a great lens.My shooting life is better because they stuck it out for so long. I don't blame them a bit for dropping Pentax. Instead I'm grateful they hung in as long as they did. There are still a pile of Pentax APS_c shooters who wouldn't be Pentax shooters without the 18-35 1.8. Let's not short sell their contribution, just because in the end it didn't work out.

It's too bad it didn't work out long haul, but that's water under the bridge.

---------- Post added 09-16-17 at 12:53 PM ----------

May I point out that your comparison of Photozone sharpness graphs is unfair as far as corner sharpness is concerned?

- the Sigma 35mm f/1.4 DG HSM | Art, AF-S Nikkor 35mm f/1,8G and AF-S Nikkor 35mm f/1,4G were tested on a Nikon D3X, a 24x36 camera
- the Canon EF 35mm f/1.4L USM, an old lens (1998) replaced in 2015, was tested on a Canon EOS 5D Mark II, a 24x36 camera
- the smlc Pentax-FA 31mm f/1.8 Limited was tested on a Pentax K-5, an APS-C camera.

Corner sharpness...

Of course it's unfair, every test is unfair, what's better?
I took a few minutes to look up a few lenses, if someone can do better that would be awesome.

I always go with best data, if someone presents better data, I change my mind, I don't change my mind for opinions offered with no data.

---------- Post added 09-16-17 at 12:55 PM ----------

sharpness scores can only be compared between the same or similar sensors

Overall lens performance and characteristics can be derived from test charts... the sharpness scores, how a lens shot on one system might score on another system cannot.

Although as a caveatt, lens characteristics can change based on different MPs. However you never see much change when the only change is which system it's used on and format and MPS are the same. If you understand the concepts it's really easy to understand what you can infer and what you can't.

The 31 on a 10 MP body was almost a perfect lens. On a 16 MP body not so perfect. NO one knows what it might look like on a K-1. What you can collect is evidence, not proof.

Collecting evidence I always go for the low having fruit. Those who want better, have at her. I await your results, but not your unsubstantiated criticism or opinion.

If Rondec wants to show some test charts or sample shots showing that the 70-200 is better for portraits at 80mm than the 77 is, I'll love it as much as anyone else. Direct evidence on the same body using both test charts and real wold samples for rendering characteristics is always the way to go. But it's also more work than most of us are willing to do.

I've been considering a test of my 50, 70, 90 and 100 macro's against each other, but even a retired guy has stuff he has to do every day.

It's easy to say Pentax can't rest on the 31 and 77, it's true. They need a wider market. Is anyone ever going to produce better lenses at that size? Now that would be open to debate. Someone tell me when someone does it, Their place in the market is well established and as far as I know, un-challenged. Some folks forget, some of us carry our gear long distances, they aren't just on the back seat of our car while we drive around.

In that particular niche, the competition is over, Pentax won, no one else is even trying to compete anymore. They are trying to convince you to buy something bigger and heavier. One of my Canon shooting buddies actually gasped when I pulled a little waterproof shockproof pelican case out of my pocket and showed him my 21 ltd and 40 xs were inside. Regardless of comments made above, those Limited Lenses are still lenses admired by many, Pentax and non Pentax shooters alike. If Nikon, Sony, Fuji and Canon don't come up with something similar, they will always be second rate companies in my book, and in the minds of those who do what I do, and right now they aren't even trying. This Pentax doesn't do what I want them to applies to every company out there. Well, Canon Sony, Nikon and Fuji aren't doing what I and many others think they should do. And they have to do it if they want our business.

[Kunzite]

But you said 'this is not exactly' how it works. Now you are telling me, in that post that you said 'this is not exactly how it works' that it is exactly how it works. /facepalm

Besides, you're changing your tune. You said, before this, "Talking doesn't accomplish much, if anything. What does the trick is us buying existing products - this, not talking, would push the manufacturers to release more. The Sigma Art lenses we're not getting? That's because we didn't buy enough of what they made in K-mount (I'm not assigning blame, just stating a fact).
When the new D FA* primes will arrive, I hope people will buy them instead of complaining about the price."

But normhead is saying "If we right now buy up every Pentax lens out there left in Sigma's inventory, Sigma could still judge Pentax mount unworkable, because of the amount of time it took to sell them and of how much of their expected profit was eaten up by the cost of keeping those lenses in inventory."

Which is contradictory to your view. Yet you are telling me "As described in the post you were quoting - and as explained by normhead." is exactly how it works. So you are saying one thing and agreeing with someone else saying another.


Either way, Mid to Long term, I suspect K mount is essentially gone from Sigma's lineup. But IIRC Adam even had someone ask Sigma reps if they would be interested in doing small made-to-order bulk sales of Sigma lenses not currently offered in K mount... where we pay first and they mail later. And they still said they had no interest in K mount. I think they really would rather see K mount die and there be one less format out there.

Just because you don't understand doesn't mean I'm wrong
When I said "this is not exactly how it works" I was referring to your post. Nobody's expecting you to buy lenses you do not want; and there's the product segmentation which was completely missing from your post. A 150-600 S is not decided by previous demand for kit lenses, for example.

Nothing normhead said in that post was in disagreement with mine's. You'd have to stop trying to find imaginary faults in my posts to see that, though...

No, Sigma has no wish to see the K-mount die. A corporate entity doesn't operate on such a personal level - and there's no business advantage for them if the K-mount is gone (since they're not competing with it).

[mee]

Just because you don't understand doesn't mean I'm wrong
When I said "this is not exactly how it works" I was referring to your post. Nobody's expecting you to buy lenses you do not want; and there's the product segmentation which was completely missing from your post. A 150-600 S is not decided by previous demand for kit lenses, for example.

Nothing normhead said in that post was in disagreement with mine's. You'd have to stop trying to find imaginary faults in my posts to see that, though...

No, Sigma has no wish to see the K-mount die. A corporate entity doesn't operate on such a personal level - and there's no business advantage for them if the K-mount is gone (since they're not competing with it).

I did not make up anything.. I quoted straight from YOU!

Talking doesn't accomplish much, if anything. What does the trick is us buying existing products - this, not talking, would push the manufacturers to release more. The Sigma Art lenses we're not getting? That's because we didn't buy enough of what they made in K-mount (I'm not assigning blame, just stating a fact).

If we right now buy up every Pentax lens out there left in Sigma's inventory, Sigma could still judge Pentax mount unworkable, because of the amount of time it took to sell them and of how much of their expected profit was eaten up by the cost of keeping those lenses in inventory.

Do you not see these two views are not the same?

You are saying the trick is us buying existing products... that is, if we want to see more K mount Sigma lenses we need to start buying more Sigma lenses. Normhead is saying even if we bought everything Sigma has already made, they could very well say it wasn't enough.

[Kunzite]

First you have to understand that what you're extracting from normhead's post is just a small part - this is not the explanation, but an additional "it might not work" hypothesis.

After you do that: no, they're not opposite (and I know how to negate a statement better than most!). What normhead is saying is there's no absolute guarantee in buying existing stocks - but I never said it is. OTOH, if we don't buy - that is absolutely guaranteed to have an effect.
Me and normhead agree in that it's all about buying / moving inventory:
"They make lenses for Pentax and they sell or they don't. If they sell fast enough, and fast enough is a thing because companies hate to store unsold inventory, they make more Pentax lenses. If they don't sell fast enough they don't make more Pentax lenses."

[normhead]

First you have to understand that what you're extracting from normhead's post is just a small part - this is not the explanation, but an additional "it might not work" hypothesis.

After you do that: no, they're not opposite (and I know how to negate a statement better than most!). What normhead is saying is there's no absolute guarantee in buying existing stocks - but I never said it is. OTOH, if we don't buy - that is absolutely guaranteed to have an effect.
Me and normhead agree in that it's all about buying / moving inventory:
"They make lenses for Pentax and they sell or they don't. If they sell fast enough, and fast enough is a thing because companies hate to store unsold inventory, they make more Pentax lenses. If they don't sell fast enough they don't make more Pentax lenses."

I'm normhead and I approve of the above analysis.

---

Last edited by normhead; 09-16-2017 at 11:07 AM.

[lukulele]

[

I've been considering a test of my 50, 70, 90 and 100 macro's against each other, but even a retired guy has stuff he has to do every day.

Thanks Norm,
I resemble that remark......
after the comma.

[normhead]

[


Thanks Norm,
I resemble that remark......
after the comma.

Does that mean you're not coming over to live in the cabin, and test my 50, 70, 90, and 100 macros against each other?

I had my hopes up there for a second.

I always believe, if you put something off long enough, someone else will do it.

[mee]

First you have to understand that what you're extracting from normhead's post is just a small part - this is not the explanation, but an additional "it might not work" hypothesis.

After you do that: no, they're not opposite (and I know how to negate a statement better than most!). What normhead is saying is there's no absolute guarantee in buying existing stocks - but I never said it is. OTOH, if we don't buy - that is absolutely guaranteed to have an effect.
Me and normhead agree in that it's all about buying / moving inventory:
"They make lenses for Pentax and they sell or they don't. If they sell fast enough, and fast enough is a thing because companies hate to store unsold inventory, they make more Pentax lenses. If they don't sell fast enough they don't make more Pentax lenses."

Ahh okay. Then you could be more specific when you say things such as

As described in the post you were quoting - and as explained by normhead.

Because when you state this you are agreeing with his whole statement which was:

They make lenses for Pentax and they sell or they don't. If they sell fast enough, and fast enough is a thing because companies hate to store unsold inventory, they make more Pentax lenses. If they don't sell fast enough they don't make more Pentax lenses. If we right now buy up every Pentax lens out there left in Sigma's inventory, Sigma could still judge Pentax mount unworkable, because of the amount of time it took to sell them and of how much of their expected profit was eaten up by the cost of keeping those lenses in inventory. SO Sigma (like Tamron) has to decide, should we make 500 lenses for Pentax mount that take 5 years to sell, or should we make another 500 lenses in Nikon mount, that require no further R&D and will be gone next year? Which do you suppose makes them more money? I assume the Sigma dropping Pentax was not only based on low Pentax sales, but on the likely hood of ever making a profit on Pentax K-mount lenses. Companies will gamble from time to time, but they like the odds to be in their favour.

Which includes the portion I quoted. It isn't a context issue on my part, because the point of his post is that Sigma crunches the numbers and determined Pentax doesn't make financial sense (due to sitting inventory). To which I and normhead agree... but that conclusion he made was an obvious given. They're a business and as a business they ALL crunch the numbers and determine if it makes sense for them or not.

But you said:

Talking doesn't accomplish much, if anything. What does the trick is us buying existing products - this, not talking, would push the manufacturers to release more. The Sigma Art lenses we're not getting? That's because we didn't buy enough of what they made in K-mount (I'm not assigning blame, just stating a fact).

You might agree with what normhead said (at which case we all 3 agree), but that wasn't the claim you stated in text. I just quoted your whole statement right here ^. If you meant something else, that's fine. But, in that case, what you said and what you mean then are two different situations. It was ambiguously vague. No worries, you just need to be more specific in the future.

[Kunzite]

mee, we (not) buying is the same thing as the producer (not) moving inventory.
And... I'm tired of your nit picking and fault seeking. This exchange is over.

[mee]

mee, we (not) buying is the same thing as the producer (not) moving inventory.
And... I'm tired of your nit picking and fault seeking. This exchange is over.

Well, not exactly. Because the reasons for not buying could be different.. and they might make a difference.

It could be that K mount lenses, in general, are just not selling much. It could be that what small selection Sigma offers in K mount are just unappealing to Pentax users (and if they offered a different assortment of lenses they would sell significantly better). Or it could be a combination of the two.

Perhaps even if we met the peak sales curve on an optimal set of lenses, it still wouldn't match what Sigma sells in F or EF mounts on those lenses. We just don't know.

But I'm not nitpicking. Ambiguousness leads discussions down different paths intended.

[normhead]

I have bought Sigma lenses when they weren't exactly what I wanted but they were close enough.... but the 8-16 I can't understand. It should be a top seller, Pentax makes no comparable lenses.

Sigma and Tamron traditionally have been the ones coming out with lenses the big producers weren't offering, or by offering lenses of lesser quality and cheaper price. The 8-16 is a lens that Pentax doesn't make, and is every thing but WR. So go figure. Two years after production ended, they still have stock.

I should do a poll, "why won't you buy a Sigma 8-16..." I'd just have to make up some responses.

The big problem now is, buying old Sigma stock is supporting a company that no longer supports Pentax. Supporting them helps support R&D for Nikon and Canon, whoever.... there's no way it gets back to supporting K-mount.

But not buying from them punishes them for ever supporting K-mount, so what can you do?

[Wheatfield]

New camera-system require new glass. Digital fullframe is new for Pentax. "make-do" time is over very soon.
Pentax is not the only manufacturer in the FF market and the old lens design will not do the trick. It makes sense to talk about new glass as Pentax is not replacing older glass, but as times goes by, we see more and more offers elsewhere, including image stabilization and performance advanatges that Pentax does not have these days. Whatever is coming should be just perfect - not just big and bright.

Even if old lenses are good enough, one has to play used market roulette to get them. This becomes a problem for attracting new users who look at what's available on some retailer's website.

[Rondec]

I post the information relevant to my thinking, lens charts, expert opinions, and that's what you offer? I'd hoped you could do better.

I always hope people think differently than I do because they know more than I do. Sometimes it's just they are more opinionated, although I find it hard to imagine being more opinionated than me. Is that even possible?

OK, I have to ask, where is this lens better than the 31 ltd. that Pentax should be looking to match or exceed?

Just so we are clear, even though this is a thread about the DFA *85 coming we are talking about roughly a 30 to 35mm focal length. From what I've seen, the Sigma 35mm is sharper corner to corner, particularly wide open. The Zeiss 35mm Milvus is a very nice lens too.

Generally speaking, what would I like to see with the FA limiteds? Improved edge sharpness, get rid of fringing, improve the coatings, add an in lens motor for silent operation and weather seal them. Add quick shift. There are a number of things they can do to modernize the FA limiteds and in the long run, I would think that would attract folks to the brand and improve sales, if that's what they are after.