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04-19-2009, 02:06 AM   #1
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where are these lenses?

Looking at Pentax line up I have to say I don't quite understand it.
They have been commited to APSC for what, 6 years now? They are making lenses with equivalent FOV compared to FF lenses and still there are several main bases left empty!
look at the primes:

DA14/2.8 = FA20/2.8
DA15/4 = wants to be 24mm replacement (I understand why they didn't make it 16mm [DA*16-50, DA16-45] but they could/should have made it 2.8 IMHO)
DA21ltd = FA31ltd (in FOV comparison only!!!)
DA35 macro = FA50 macro
DA40 = ... kind of oddball but still a nice lens
DA*55 = FA*85
DA70 = 105mm another oddball length but another nice lens

did I leave something out?
longer telephotos but there many would argue about the magnification 200 = 200 and not 300 even if it's FOV is similar... and I agree with this,
please remember that I understadn this is true even with shorter FL but for the sake of commitment of replacing the line up in terms of FOV let's not argue about it...

looking at that, it still leaves us with unforgivable gaps:
where are lenses to replace:
fast 50??? one of the basics of photography? The only options available are 31/1.8 (expensive) 35/2 (slower) Sigma 30/1.4 (3rd party)
35/2 popular moderate wide/fast wide angle, there is absolutely nothing to take it's place else then FA*24 (expensive and discontinued) and Sigma 24/1.8
28/2.8 standard wide angle! It's been like that for generations of lenses (I'd be even happy with f3.5 equivalent) but there's nothing to replace it (unles you don't count SMC 18/3.5 and yes that's K generation!!!)
135/2.8 or 3.5 there was a huge number of these and yet in digital era there's no replacement other then Tamron's 90/2.8 macro

well, that's for the commitment, we have nice zoom line up, covering each (with exception of 12-16) focal length like 2-3 times, but yet in primes secoter (pride of Pentax system) there are gaps which seem unforgivable to me, makes me feel just a bit sad...

BR

04-19-2009, 03:46 AM   #2
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I guess, the Pentax line-up - apart from the aparent idiosyncrasies - reflects the move towards zoom lenses in general. So we have covered the 16-50mm range threefold with different quality and price tagged lenses. We have loads of discussions about the merrits of prime lenses in this forum - but that does not reflect the needs or wishes of 90% of all customers (aka consumers), who simply want to have the convenience of zooms.

Unfortunately Pentax does not even go the zoom route with enough resolution, as otherwise the sad 60-250-story would hardly be explainable...

Ben
04-19-2009, 08:58 AM   #3
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A lot of what I'm saying here is nothing particularly new - this is a recurring discussion, as I'm sure you know. But for the record:

QuoteOriginally posted by axl Quote
did I leave something out?
The 50 and 100 D-FA macros if the the goal is to list all lenses with some sort of "digital" connection as opposed to just the lenses designed for APS-C.

QuoteQuote:
(re: longer telephotos) but there many would argue about the magnification 200 = 200 and not 300 even if it's FOV is similar... and I agree with this
Until someone invents a way to see the image on the sensor rather than requiring you to view it on screen or print it, this "magnification" does not matter. What matters is FOV and the *resolution* you achieve at that FOV. If a 200mm lens on APS-C can produce the same *resolution* as a 300mm lens on FF, then it does everything it needs to do.

QuoteQuote:
please remember that I understadn this is true even with shorter FL but for the sake of commitment of replacing the line up in terms of FOV let's not argue about it...
If by that you mean, you are willing to accept that a 200mm lens on APS-C is a substitute for a 300mm on FF in *exactly* the same way that a 35mm is for a 50mm, then OK. If you're going to insist on an irrelevant distinction between shorter and longer FL's, then not OK.

QuoteQuote:
fast 50??? one of the basics of photography? The only options available are 31/1.8 (expensive) 35/2 (slower) Sigma 30/1.4 (3rd party)
I agree, would be nice to have something there. On the other hand:

- The registration distance is such that it seems a fast normal cannot be made for APS-C as small or as cheap as it could for full frame. Note I don't have the optics background to prove this, but it seems to be the conventional wisdom, and in the absence of good evidence to the contrary, I accept it at face value.

- One reason why 50 was "one of the basics of photography" is that it was a decent compromise focal length in the days when decent zooms weren't available. With the existence of modern zooms, "compromise" focal lengths like the so-called "normal" become less interesting for primes, compared to focal lengths that are well suited to specific purposes.

- One reason why apertures larger than f/2 were so important to film photography was that higher ISO's were not feasible - the only way to get handholdable shutter speeds was larger apertures. With ISO 1600 on digital being about as good as ISO 400 on film, that's basically a two-stop advantage right there. Also factor in SR. So the *need* for larger apertures is rather less. Yes, I know - increasing ISO or engaging SR don't give you any more DOF control. I said the need was reduced, not eliminated. And with reduced need comes reduced market - even more so when one considers the higher price made necessary by the registration distance at this focal length.

Similar factors to apply to pretty much all the other lenses you mention. Zooms have changed everything in terms of selection of focal lengths; the sensor size / registration distance ratio affects the size/cost of building a given type of lens, and the need for speed is reduced. None of which means primes don't make sense any more, but it's kind of misleading to assume the specific primes that make the most sense are the ones that reproduce the specific FOV/aperture combos that were popular on film.

QuoteQuote:
135/2.8 or 3.5 there was a huge number of these and yet in digital era there's no replacement other then Tamron's 90/2.8 macro
I suppose if you choose to discount the D-FA100/2.8 macro, that would be true. But I don't know that it makes sense for Pentax to act as if they don't already have a lens that can fill that niche. Of course, it's not as cheap as 135's used to be, so I'd definitely be in favor of a more affordable option here. Or are you saying that the difference in FOV between 90mm and 100mm is significant enough that 90mm is really needed despite the existence of a 100mm lens in the lineup?
04-19-2009, 11:18 AM   #4
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QuoteOriginally posted by Marc Sabatella Quote
A lot of what I'm saying here is nothing particularly new - this is a recurring discussion, as I'm sure you know. But for the record:



The 50 and 100 D-FA macros if the the goal is to list all lenses with some sort of "digital" connection as opposed to just the lenses designed for APS-C.

but they are not digital designs, it's still just plain old FA design with some added coatings...



Until someone invents a way to see the image on the sensor rather than requiring you to view it on screen or print it, this "magnification" does not matter. What matters is FOV and the *resolution* you achieve at that FOV. If a 200mm lens on APS-C can produce the same *resolution* as a 300mm lens on FF, then it does everything it needs to do.



If by that you mean, you are willing to accept that a 200mm lens on APS-C is a substitute for a 300mm on FF in *exactly* the same way that a 35mm is for a 50mm, then OK. If you're going to insist on an irrelevant distinction between shorter and longer FL's, then not OK.

Lens is a lens, no matter what. No matter what size of medium you put it on. The enlargement provided by lens remains constant! How much of the picture projected by the lens is sensor/film capable of recording is whole another thing, together with enlarging needed to print.

I agree, would be nice to have something there. On the other hand:

- The registration distance is such that it seems a fast normal cannot be made for APS-C as small or as cheap as it could for full frame. Note I don't have the optics background to prove this, but it seems to be the conventional wisdom, and in the absence of good evidence to the contrary, I accept it at face value.

look at FA35/2 is it big? no it's not, it wouldn't be a big problem to make it 1.7 without enlarging it too much, though as you I don't have background in optical engineering so what do I know, but if Nikon guys managed why on earth Pentax guys can't???

- One reason why 50 was "one of the basics of photography" is that it was a decent compromise focal length in the days when decent zooms weren't available. With the existence of modern zooms, "compromise" focal lengths like the so-called "normal" become less interesting for primes, compared to focal lengths that are well suited to specific purposes.

what if one doesn't like compromises?!? Plus, there isn't zoom faster than f2.8...

- One reason why apertures larger than f/2 were so important to film photography was that higher ISO's were not feasible - the only way to get handholdable shutter speeds was larger apertures. With ISO 1600 on digital being about as good as ISO 400 on film, that's basically a two-stop advantage right there. Also factor in SR. So the *need* for larger apertures is rather less. Yes, I know - increasing ISO or engaging SR don't give you any more DOF control. I said the need was reduced, not eliminated. And with reduced need comes reduced market - even more so when one considers the higher price made necessary by the registration distance at this focal length.

High ISO can deliver handholdable shots, but can't deliver narrow DOF that appertures of f2, f1.7, 1.4 and 1.2 could.... IMHO, you said it yourself, plus even with modern DLSRs you are loosing DR when increasing ISO. DSLRs have lower DR than film as it is why should we sacrifice even more by increasing ISO...

Similar factors to apply to pretty much all the other lenses you mention. Zooms have changed everything in terms of selection of focal lengths; the sensor size / registration distance ratio affects the size/cost of building a given type of lens, and the need for speed is reduced. None of which means primes don't make sense any more, but it's kind of misleading to assume the specific primes that make the most sense are the ones that reproduce the specific FOV/aperture combos that were popular on film.

Zooms are big!! and require more engineering, more moving parts, more things to break... I'd rather have bag full or primes, size of FA28, 35 and 50...



I suppose if you choose to discount the D-FA100/2.8 macro, that would be true. But I don't know that it makes sense for Pentax to act as if they don't already have a lens that can fill that niche. Of course, it's not as cheap as 135's used to be, so I'd definitely be in favor of a more affordable option here. Or are you saying that the difference in FOV between 90mm and 100mm is significant enough that 90mm is really needed despite the existence of a 100mm lens in the lineup?

DFA100 is dedicated macro lens, it's good but it's still macro. I'm forced to use Sigma 105 macro in role of medium tele, and boy do I wish to have something that would do zm, zm and lock instead of zoooooooooooooom, zoooom, zom, zm of the macro.... that's the biggest disatvantage IMHO
see above, please
BR

04-19-2009, 01:10 PM   #5
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QuoteOriginally posted by axl Quote
see above, please
BR
Axl, you reply to Marc, that "one may not like compromises". So, if that is the truth, there is no lack of "fast fifties" replacement on the Pentax APS-C side: the 31mm Ltd. or the Sigma 30mm would fullfil that role. One point less to complain about.

The real lack in the Pentax lens portfolio is, as I see it (but everybody will discover his own favourite holes), are long focal lengthes and especially fast ones. And fast short primes.

Pentax has made a decision to sacrifice fast lenses for the sake of smaller and more lightweight ones (like they did during the 70s with the M lenses and bodies). It is a business decesion and I have to accept that. Seeing, how many photogs here and elswhere are happy with that route, Pentax seems about to be right with that part of the lens roadmap. I personally do not need a 40/2.8, 21/3.2 etc. These lenses are simply too slow in my opinion, But then, I am sure not representative for the majority of customers.

And I cannot see any other manufacturer which would really fullfil my needs better than Pentax (all in all). I see some lenses, I would love to have in the Nikon lineup, others in the Canon or Olympus portfolio. But all in all the Pentax system is a good compromise solution for my needs, even if I miss a few things.

Ben
04-19-2009, 01:21 PM   #6
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QuoteQuote:
but they are not digital designs, it's still just plain old FA design with some added coatings...
True. I guess the question is, why is this distinction important? Does it in some way make the lens less usable on digital than they would be otherwise? Focus speed - now that's a distinction worth making.

QuoteQuote:
Lens is a lens, no matter what. No matter what size of medium you put it on. The enlargement provided by lens remains constant!
This is true also, but has no real world relevance whatsoever. The amount of "enlarging" done by a lens is not what determines the appearance or quality of the picture. As I said before, what matters is the FOV and the resolution provided. A 5-50mm zoom lens designed for a P&S with a 6X "crop factor" might produce a much smaller image at 50mm than a 300mm lens designed for FF. But if the resolution of the sensors are the same, and the lens resolves well enough to take advantage of the senor resolution, you're not going to see any benefits whatsoever to the greater "magnification" the 300mm lens provided. It's simply a myth to assume you will. There is no way to tell in the example I just gave which system will in fact perform better with regard to any aspect of image quality (except of course high ISO noise, where you'd assume the larger sensor wins - but that has nothing to do with any difference between the lenses).

Now, one might wonder how *typical* it would be to have a shorter lens for a smaller format to have resolution to match the longer lens for the larger format. I don't have an answer for that, and I doubt you do either. What I can say is that I certainly don't see any reason to simply *assume* that the long lens for the large format will have more real resolution than the short lens for the small format - particularly when we are talking about the relative small differences between 35mm and APS-C as opposed to the relatively large differences between 35mm and a P&S.

QuoteQuote:
look at FA35/2 is it big?
Not really, although it *is* bigger than any 50/2. But you're probably right - the *size* might not be as significant a factor at the 35mm focal length so much as the cost. AFAIK, 35/2's pretty much always cost much more than 50/2's.

QuoteQuote:
what if one doesn't like compromises?!?
That's my point. 50mm *is* a compromise (between FOV, price, and size) that happened to make sense on 35mm film cameras. Why get so hung up on reproducing one aspect of that compromise (FOV) on APS-C? I mean, if it were the best possible focal length for some purpose, that would be worth reproducing. But it isn't really - it's just a decent focal length if you are trying to design a small cheap prime for someone who probably doesn't own any other lens in any other focal length. In today's world, there just aren't that many people fitting that description.

QuoteQuote:
High ISO can deliver handholdable shots, but can't deliver narrow DOF that appertures of f2, f1.7, 1.4 and 1.2 could.... IMHO, you said it yourself
I did indeed. I also added that the need for speed was reduced, not eliminated, but that with reduced need comes reduced demand. In the absence of usable zoom lenses, and in a world where f/2 or better was needed to get handheld shots in even moderately low light at ISO 400, demand for such a fast 50 was *enormous*. Pentax sold a zillion of them because virtually every single person who bought a camera bought a fast fifty with it. I doubt Pentax would sell even 10% as many fast 35's to today's DSLR owners as they did to yesterday's 35mm SLR owners. That's got to factor in to any decisions on which lenses to produce.

QuoteQuote:
Zooms are big!! and require more engineering, more moving parts, more things to break... I'd rather have bag full or primes, size of FA28, 35 and 50...
Hey, don't get me wrong, I'm not saying zooms are the answer for everyone. I prefer primes too most of the time. I'm just trying to be realistic about what the demand for these lenses really is. Primes are a much tougher sell in today's market than zooms are; that's just how it is. And with prime sales being down overall, it doesn't really surprise me that a lens manufacturer would concentrate on higher margin "specialty" primes as opposed to the more general purpose sorts of lenses they used to crank out and sell cheap on volume.

Basically, the way I see it is, Pentax is not stupid. If they thought there was a huge demand for primes with the specs you describe, and they could meet that demand at a price point that would sell in the sort of numbers necessary to turn a better profit than the lenses they are producing instead, they'd be there in a minute. Wouldn't anyone? I don't think we need any sort of conspiracy theories to explain why this isn't happening. I think it is as simple as I am saying - they aren't doign this because the demand probably isn't there for lenses that would probably cost what these lenses would have to cost to make money.
04-19-2009, 01:28 PM   #7
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Splitting hairs

QuoteOriginally posted by axl Quote
The 50 and 100 D-FA macros if the the goal is to list all lenses with some sort of "digital" connection as opposed to just the lenses designed for APS-C.

but they are not digital designs, it's still just plain old FA design with some added coatings...
BR
Maybe not designed for APS-C but I'm sure you could argue that they were sufficiently modified (check the element map and descriptions) to be "re-designed" for digital...
The 50mm was subject to sensor flare and now it isn't (D-FA) ect.
DFA100 and FA100 is different as well..... see these:

04-19-2009, 01:53 PM   #8
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by "they are not digital" I basicaly mean they are not meant to replace FF 50 & 100 in terms of FOV. If they would be they would've been 35 ish (we have that one) and 70ish (there is Sigma version...)

04-19-2009, 01:59 PM   #9
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QuoteOriginally posted by Ben_Edict Quote
Axl, you reply to Marc, that "one may not like compromises". So, if that is the truth, there is no lack of "fast fifties" replacement on the Pentax APS-C side: the 31mm Ltd. or the Sigma 30mm would fullfil that role. One point less to complain about.

.....

Pentax has made a decision to sacrifice fast lenses for the sake of smaller and more lightweight ones (like they did during the 70s with the M lenses and bodies). It is a business decesion and I have to accept that. Seeing, how many photogs here and elswhere are happy with that route, Pentax seems about to be right with that part of the lens roadmap. I personally do not need a 40/2.8, 21/3.2 etc. These lenses are simply too slow in my opinion, But then, I am sure not representative for the majority of customers.
...
Ben
higlhlight 1:
31 is not a compromise, not at all, the oposite is probably the truth as it is probably the best option we have, but it's not lens for many either. It's price tag is on the highter side and as such, not everybody can get it. I got lucky and got it 1/2 price, otherwise I wouldn't really contemplate even getting it, and as for Sigma, it may be a decent lens, but it is a compromise as it basicaly forces Pentax users to go 3rd party way...

highlihgt 2:
if you shoot in the dark/evening then yes, it may be slow, but for streets, tourism, landscapes, towns it's more then enough...

BR
04-19-2009, 02:12 PM   #10
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QuoteOriginally posted by axl Quote
if you shoot in the dark/evening then yes, it may be slow, but for streets, tourism, landscapes, towns it's more then enough...
That is certainly true - and that is the reason, why I wrote, that my personal opinion is that of a tiny minority and does not represent the feeling of the majority of Pentax customers.

What I wanted to emphasize with this and the other examples is: Pentax has chosen a strategy for their product development, which leaves gaping holdes in their line-up. But for the majority of customers, this is acceptable, even if in each individual case, there will be some feeling of missing a certain lens. So, all in all, Pentax seems to have a good basic understanding of what really sells in their market.

Ben
04-19-2009, 02:42 PM   #11
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QuoteOriginally posted by Marc Sabatella Quote
- The registration distance is such that it seems a fast normal cannot be made for APS-C as small or as cheap as it could for full frame. Note I don't have the optics background to prove this, but it seems to be the conventional wisdom, and in the absence of good evidence to the contrary, I accept it at face value.
There was an absence of evidence until like two months ago. Now, there is the Nikon 35/1.8. $219.95. Pentax -- do this!
04-19-2009, 02:42 PM   #12
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Peter, I know the frustration of trying to get these lenses. This is the legacy of Pentax.

Still, lens availability issue is already improving as these lenses are still available for purchase once in a while off the internet stores.

A lot of so-called legendary pentax lenses were so scarce, being given ultimate superior status and a incredibly high price tag in the second hand market. I did regret buying some of these lenses myself.


Still, pentax primes are special. Besides some setback on PF, they do have that special look to them all with stunning contrast with a more affordable prices than canikon brands
04-19-2009, 02:58 PM   #13
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QuoteOriginally posted by axl Quote
135/2.8 or 3.5 there was a huge number of these and yet in digital era there's no replacement other then Tamron's 90/2.8 macro

well, that's for the commitment, we have nice zoom line up, covering each (with exception of 12-16) focal length like 2-3 times, but yet in primes secoter (pride of Pentax system) there are gaps which seem unforgivable to me, makes me feel just a bit sad...

BR
I generally agree that Pentax lenses have covered the range <100mm quite well. But the scene is entirely different >100mm

There is zero around 135mm except maybe the DA*50-135mm

At 135mm the FA version AF speed is more than matching that of the SDM AF speed of the DA*zoom.

If only Pentax can reissue FA135mm (same optics) like DA*200mm (same optics of FA*200mm plus sdm + weatherseal), I would go for it. It certianly would not take too much effect. I would not care fringing in extreme contrast situation (DA*200mm & FA135mm) which is more like a nuisance than a defect


Daniel

Last edited by danielchtong; 04-19-2009 at 03:03 PM.
04-19-2009, 03:09 PM   #14
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QuoteOriginally posted by Marc Sabatella Quote
Hey, don't get me wrong, I'm not saying zooms are the answer for everyone. I prefer primes too most of the time. I'm just trying to be realistic about what the demand for these lenses really is. Primes are a much tougher sell in today's market than zooms are;
I am in agreement. Younger shooters (the majority I have to say) just take time to understand manual focus, manual metering and prime lens shooting.
My response to those doubter is always to tell them to look at the images of both camps. That tells a lot

Daniel
04-19-2009, 03:22 PM   #15
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Maybe they don't sell may due to their backwards compatibility.... Instead of shelling out the coins for a shiny new one lots and lots of pentaxians come here or to fleabay and buy the lovely old primes. This leaves less money in Pentaxs' pocket.

mike
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