[philmorley]

I dont think they will in a hurry, when almost every lens now is da.

But with their capacity to design and produce their own sensors (obv. with samsung) they at least have options now, and dont have to try and compete with the manufacturer of a key component of their product.

To my thinking though, many of the da lenses would work on aps-h which would give them what 18-20 mp??? (I too lazy to do the math and I think this route would be more likely than FF (but then what do I know LOL)

edit: the more I think about it, the less likely I think ff is. They mentioned last year that would like to release 20 odd lenses that they have designs of, but dont have the manufacturing capacity to do so. I think that expecting them to produce a range of ff lenses as well as the da's is unrealistic, even though they have designs for he ff's as well. (the argument of old lenses isn't really profitable for pentax, they want you to buy new ones, and I would think its hard to market a camera that has a salesline if you want to buy lenses you have to go on ebay.) - Then again Pentax aren't always logical

Phil

---

Last edited by philmorley; 01-30-2008 at 04:44 PM.

[Andrew Faires]

To my thinking though, many of the da lenses would work on aps-h which would give them what 18-20 mp??? (I too lazy to do the math and I think this route would be more likely than FF (but then what do I know LOL)

Just based on my 2 DA lenses, from what I've seen with the 14mm on my MX, it would be hard-pressed to cover anything but APS-C. However, my DA* 16-50 has a much larger rear element and vignettes much less on my MX. I'd wager it would cover aps-H without difficulty.

[*isteve]

I don't get some of the replies to FF.


So, we want 35mm for simplicity, for proper perspective, for reasonable wide solutions that don't skew perspective, etc.

Who are "we"? Speak for yourself.

I am perfectly happy with focal lengths on APS cameras, just as I was happy converting from 645 to 35mm 20 years ago. There is no "proper" FL to perspective ratio, it has ALWAYS depended on the film and sensor format.

Specious argument.

[vinzer]

I really don't care much for FF, but I think the development by Sony of a FF camera would be more of to say that they're serious in the DSLR space and in the pro segment of the market more than generating actual sales of the A900 (well, if they eventually make money out of it, that's a plus).

Unlike the P&S crowd, some (not all) people looking to buy DSLRs are also conscious of an upgrade path in the future, which is partly why people choose to buy Canon or Nikon (among other reasons).

While some of us are happy with our K10D's and K20D's (in the future), other Pentax users are already speculating on a possible K1D in the future, which speaks a lot about more about the perceived importance of an upgrade path than the actual need for such a camera.

And then there are those (pros) who really have need of such a camera. Whether or not Pentax goes APS-C, APS-H, 135, or 645 format remains to be seen, though.

[Marcus]

Sony just announced a 24.8MP CMOS FF sensor that will be used in their pro model later this year.

That is going to be one HUGE file. That will be one monster of a camera. A big slow monster.

Even at Sports Illustrated in PopPhoto for February, SI said that it's not about resolution anymore. Because last years 8.2 MP from Id Mark IIN gave 10-12 MB files for RAW +JPEGs. That was more than fine. With this new 24.8MP sensor, we're probably talking 25-30MB files here! Sony is on steroids, and not in a good way.

This definitely won't be a camera for the sports shooter, I hope. But for WHO exactly?

[nathancombs]

That is going to be one HUGE file. That will be one monster of a camera. A big slow monster.

Even at Sports Illustrated in PopPhoto for February, SI said that it's not about resolution anymore. Because last years 8.2 MP from Id Mark IIN gave 10-12 MB files for RAW +JPEGs. That was more than fine. With this new 24.8MP sensor, we're probably talking 25-30MB files here! Sony is on steroids, and not in a good way.

This definitely won't be a camera for the sports shooter, I hope. But for WHO exactly?

"promises to output all pixels at 6.3 fps"

that is better then the 3fps

[24X36NOW]

Maybe the question needs to be framed this way: If you had a choice between APS-C and Full Frame, and the prices of those two cameras allowed you to afford either one, which would you buy? It's a no-brainer. Full Frame wins hands down. There's so much speculation about how expensive such a camera "has" to be, when I don't think we've got anyone from the Pentax BOD on here lol.

Pentax NEEDS to make a Full Frame dSLR, because it is being left behind in the marketplace. Whether people "NEED" more IQ is not the point. People will WANT more IQ if it is available, regardless of their "needs." Unless you are a professional photographer, you don't "need" a digital SLR at all. You buy one because you WANT one. APS-C is an inferior format, because it is smaller than 24 x 36 (with all of the inherent disadvantages of a smaller format) without providing any equipment size/weight reduction of any significance and in fact uses a lens mount designed to support 24 x 36. It is a compromise that did not arise from any quality/convenince balancing act (which is what made 35mm popular) but to reduce COST. That is the ONLY reason APS-C format dSLRs exist - COST. If the technology for sensor chips allowed 24 x 36 sensor chips to be cheaper from the start, you would have never seen an APS-C dSLR, period. However, technology marches on. All you need do is look at the relative prices for dSLRs and the sophistication/feature levels of those products over the last 5 - 7 years and you can see it clearly. I paid $1800 for an *istD with a mere 6 megapixels just a few years ago. In April, I'll be able to buy a K20D with 14.6 megapixels for at least $500 LESS (it'll be more than that once a "street" price is established). The advance toward Full Frame is inevitable, because of the inherent compromise of APS-C and because the cost will keep getting more reasonable until more and more people are willing to pay the extra fare to get better cameras.

There's tons of talk here about how APS-C format is "good enough," but I suspect that this is much the same as people who said that a digital point and shoot was "good enough" until they could afford a digital SLR. THEN, suddenly the digital point and shoot wasn't "good enough" any more. :ugh: When Full Frame digital SLRs are more affordable, all the "I have no interest" crowd will be buying them, guaranteed.

I'm sure there will be plenty of defensive comments regarding those who will defend the compromised APS-C format to the death since they have invested in it and don't feel comfortable with "their" cameras being criticized, so let's examine some of the so-called "advantages" in the harsh light of reality:

FIRST, the much-worshipped "telephoto advantage:" This one is pure agricultural commodity (read: BS) cooked up by camera maker marketing departments and swallowed hook, line and sinker by many who are going a long way towards proving P.T. Barnum right. The focal length of a lens does NOT increase when you put it on a smaller format camera. The magnification of a lens does NOT increase when you put it on a smaller format camera. You do NOT NEED A LONGER FOCAL LENGTH LENS ON A FULL FRAME CAMERA TO TAKE THE SAME PICTURE WITH THE SAME MAGNIFICATION AS YOU CAN TAKE ON A SMALLER FORMAT CAMERA - all you need to do to get the EXACT SAME picture on a Full Frame camera is CROP the Full Frame picture down to the size of the smaller format. You DO NOT GAIN A THING - YOU ONLY LOSE SOMETHING - 58% of your image size.

SECOND, the supposed "size/weight reduction" of (in particular) "digital only" lenses designed to cover a smaller image circle rather than the full 24 x 36 frame. More agricultural commodity! Let's see how the specs of the two new "digital only" tele primes recently announced compare with their predecessors:

DA* 200 F 2.8 - 83mm wide x 134 mm long; 825 grams
FA 200 F 2.8 - 83mm wide x 134mm long; 785 grams
A 200 F 2.8 - 91mm wide x 138mm long; 850 grams

DA* 300 F 4.0 - 83mm wide x 184mm long; 1,070 grams
FA 300 F 4.5 - 73mm wide x 160mm long; 935 grams (no F 4.0 available)
A 300 F 4.0 - 84mm wide x 132mm long; 850 grams

The APS-C "digital only" lenses not only are not smaller and lighter by any significant amount, THEY ARE ACTUALLY LARGER AND HEAVIER than some comparable 24 x 36 format lenses. Certainly there is NOT sufficient downsizing of size OR weight to justify LOSING 58% OF YOUR ORIGINAL IMAGE SIZE! However, once again defenders of the compromise "crop cameras" tout this non-existent "advantage." You've been sold a bill of goods again!

THIRD, the "size doesn't matter, only image quality matters" argument. This I'm sorry to say is self-contradictory. LARGER FORMAT PHOTOS HAVE SUPERIOR IMAGE QUALITY TO SMALLER FORMAT PHOTOS, BECAUSE LESS ENLARGEMENT (MAGNIFICATION) IS REQUIRED TO PRODUCE ANY GIVEN PRINT SIZE. This is why large format is better than medium format, medium format is better than 35mm, 35mm is better than APS, and APS is better than 110. THIS WILL NOT CHANGE REGARDLESS OF TECHNOLOGY ADVANCES, since any such advances will be applied to sensor chips of both formats. Further, Full Frame sensor chips can reduce pixel density and thus noise as compared with APS-C sensor chips while maintaining superior image quality. Even at equivalent pixel density, Full Frame provides less amplification of existing noise (again, due to reduced magnification) and thus superior IQ. (It's the same reason thumbnail sensors with similar megapixels produce inferior IQ as compared with the larger sensors in dSLRs.)

FOURTH, the "file size is too big" non-issue. Memory has gotten amazingly cheap and amazingly compact. Buffer sizes, etc. can be increased as necessary to accommodate ever larger files without any problem (20+ megapixel cameras already offer 5fps, which is more than adequate for ANY photographer; until late in the film-only years, 5 fps was the most you got with motor drives even on "professional" cameras). Technology will continue to enable faster processing and greater storage, so this is a meaningless "issue."

In short, APS-C offers NO operational advantages, NO appreciable size/weight advantages, and inferior IQ. The ONLY "advantage" about APS-C is that it is CHEAPER. And as the old saying goes, "you get what you pay for." So please, stop rationalizing about APS-C format as being a replacement for 24 x 36. It's not. Rather, it's just a stop-gap whose coffin is (albeit, slowly) being constructed as Full Frame inexorably becomes more mainstream (which will bring prices down). Full Frame is the future, and Pentax needs to get with the program. Once it becomes more affordable (and it will, because that is the nature of technological advance), nobody in their right mind will want a camera of similar size and weight in a smaller image format, because aside from cost differential there is NO BENEFIT (highly successful marketing BS notwithstanding lol).

[Marcus]

"promises to output all pixels at 6.3 fps"

that is better then the 3fps

Oh boy. :ugh:

If Sony can get its game together, this might a nail in the coffin for CanCan.

24X36, that was a MAN sized post!

With Sony knocking on the door, I don't know if Pentax will have to get with the FF program sooner or later. For truepro-sumers, I don't think so. It all depends on the pricing. If FF prices drop, then APC-C size will drop. Pentax will still have prosumers ready to buy their APS-C sized cameras if they're at a good price, which I believe will be the case. It's all about timing for a Pentax FF...

Either way, I certainly won't buy it.

[jeff1101]

There is an amazing amount of logic in that justifiably long statement...

I for one am pro APS-C only because of

1) my already invested equipment and
2) Its the only format I could afford (currently)

But I think the heart of the matter, and as you put it succintly if money was no object and I was offered a choice between a FF camera and an APS-C cam (both preferably from Pentax )

I'd choose FULL FRAME. I mean its a no brainer...

[ricardobeat]

Maybe the question needs to be framed this way: If you had a choice between APS-C and Full Frame, and the prices of those two cameras allowed you to afford either one, which would you buy? It's a no-brainer. Full Frame wins hands down. There's so much speculation about how expensive such a camera "has" to be, when I don't think we've got anyone from the Pentax BOD on here lol.

Pentax NEEDS to make a Full Frame dSLR, because it is being left behind in the marketplace. Whether people "NEED" more IQ is not the point. People will WANT more IQ if it is available, regardless of their "needs."

Same goes for 645D I guess. Does Pentax NEED to make a 645 dSLR? It is being left behind in the marketplace by Hasselblad and others.

FIRST, the much-worshipped "telephoto advantage:" This one is pure agricultural commodity (read: BS) cooked up by camera maker marketing departments and swallowed hook, line and sinker by many who are going a long way towards proving P.T. Barnum right. The focal length of a lens does NOT increase when you put it on a smaller format camera. The magnification of a lens does NOT increase when you put it on a smaller format camera. You do NOT NEED A LONGER FOCAL LENGTH LENS ON A FULL FRAME CAMERA TO TAKE THE SAME PICTURE WITH THE SAME MAGNIFICATION AS YOU CAN TAKE ON A SMALLER FORMAT CAMERA - all you need to do to get the EXACT SAME picture on a Full Frame camera is CROP the Full Frame picture down to the size of the smaller format. You DO NOT GAIN A THING - YOU ONLY LOSE SOMETHING - 58% of your image size.

Might sound BS technically speaking, but in practice that's not the way it works. When you crop, you waste sensor space and get LESS resolution. To effectively get the same APS-C image from a full-frame sensor you need the FF to have the same pixel density as the APS-C one - but then some of the advantages would be lost. People don't like to waste pixels.

SECOND, the supposed "size/weight reduction" of (in particular) "digital only" lenses designed to cover a smaller image circle rather than the full 24 x 36 frame. More agricultural commodity! Let's see how the specs of the two new "digital only" tele primes recently announced compare with their predecessors:

DA* 200 F 2.8 - 83mm wide x 134 mm long; 825 grams
FA 200 F 2.8 - 83mm wide x 134mm long; 785 grams
A 200 F 2.8 - 91mm wide x 138mm long; 850 grams

DA* 300 F 4.0 - 83mm wide x 184mm long; 1,070 grams
FA 300 F 4.5 - 73mm wide x 160mm long; 935 grams (no F 4.0 available)
A 300 F 4.0 - 84mm wide x 132mm long; 850 grams

Far off. This lenses are not new designs, they are the FA lenses in new clothing and with added SDM. As far as I know there are no weightless motors, and these lenses cover full-frame.

A better comparison would be between the Tamron 70-200mm 2.8, which is the lightest of it's class at 1.1kg, and the DA* 50-135mm 2.8, weighing at 685g.

As for the rest of the rant, I really don't get it. "Bigger is better" can only hold true to a certain amount, the ideal sizing depends on technology, and we have had quite an advance in that area. It's not because 35mm was the standard for 60 years that it will remain forever. Lighten up.

[nathancombs]

i have not bought any digtal only lens and am not going to i do have the kit 18-55 but i staying with "film" lens becuse IF FF is the way things go i am not going to be stuck with lens that i can not use. that and i have like most on hear have film bobys ( K1000, P3N) that i LIKE and what is the use of having all that good glass and not be able to use them on my film bodys. 100% bacwords copatablty sort of gose out the windo and that is one of the BIGEST resons i bought Pentax.

i am out on the FF and APC debate i see the + and - of both

[Tbear]

Maybe the question needs to be framed this way: If you had a choice between APS-C and Full Frame, and the prices of those two cameras allowed you to afford either one, which would you buy? It's a no-brainer. Full Frame wins hands down. There's so much speculation about how expensive such a camera "has" to be, when I don't think we've got anyone from the Pentax BOD on here lol.

Pentax NEEDS to make a Full Frame dSLR, because it is being left behind in the marketplace. Whether people "NEED" more IQ is not the point. People will WANT more IQ if it is available, regardless of their "needs." Unless you are a professional photographer, you don't "need" a digital SLR at all. You buy one because you WANT one. APS-C is an inferior format, because it is smaller than 24 x 36 (with all of the inherent disadvantages of a smaller format) without providing any equipment size/weight reduction of any significance and in fact uses a lens mount designed to support 24 x 36. It is a compromise that did not arise from any quality/convenince balancing act (which is what made 35mm popular) but to reduce COST. That is the ONLY reason APS-C format dSLRs exist - COST. If the technology for sensor chips allowed 24 x 36 sensor chips to be cheaper from the start, you would have never seen an APS-C dSLR, period. However, technology marches on. All you need do is look at the relative prices for dSLRs and the sophistication/feature levels of those products over the last 5 - 7 years and you can see it clearly. I paid $1800 for an *istD with a mere 6 megapixels just a few years ago. In April, I'll be able to buy a K20D with 14.6 megapixels for at least $500 LESS (it'll be more than that once a "street" price is established). The advance toward Full Frame is inevitable, because of the inherent compromise of APS-C and because the cost will keep getting more reasonable until more and more people are willing to pay the extra fare to get better cameras.

There's tons of talk here about how APS-C format is "good enough," but I suspect that this is much the same as people who said that a digital point and shoot was "good enough" until they could afford a digital SLR. THEN, suddenly the digital point and shoot wasn't "good enough" any more. :ugh: When Full Frame digital SLRs are more affordable, all the "I have no interest" crowd will be buying them, guaranteed.

I'm sure there will be plenty of defensive comments regarding those who will defend the compromised APS-C format to the death since they have invested in it and don't feel comfortable with "their" cameras being criticized, so let's examine some of the so-called "advantages" in the harsh light of reality:

FIRST, the much-worshipped "telephoto advantage:" This one is pure agricultural commodity (read: BS) cooked up by camera maker marketing departments and swallowed hook, line and sinker by many who are going a long way towards proving P.T. Barnum right. The focal length of a lens does NOT increase when you put it on a smaller format camera. The magnification of a lens does NOT increase when you put it on a smaller format camera. You do NOT NEED A LONGER FOCAL LENGTH LENS ON A FULL FRAME CAMERA TO TAKE THE SAME PICTURE WITH THE SAME MAGNIFICATION AS YOU CAN TAKE ON A SMALLER FORMAT CAMERA - all you need to do to get the EXACT SAME picture on a Full Frame camera is CROP the Full Frame picture down to the size of the smaller format. You DO NOT GAIN A THING - YOU ONLY LOSE SOMETHING - 58% of your image size.

SECOND, the supposed "size/weight reduction" of (in particular) "digital only" lenses designed to cover a smaller image circle rather than the full 24 x 36 frame. More agricultural commodity! Let's see how the specs of the two new "digital only" tele primes recently announced compare with their predecessors:

DA* 200 F 2.8 - 83mm wide x 134 mm long; 825 grams
FA 200 F 2.8 - 83mm wide x 134mm long; 785 grams
A 200 F 2.8 - 91mm wide x 138mm long; 850 grams

DA* 300 F 4.0 - 83mm wide x 184mm long; 1,070 grams
FA 300 F 4.5 - 73mm wide x 160mm long; 935 grams (no F 4.0 available)
A 300 F 4.0 - 84mm wide x 132mm long; 850 grams

The APS-C "digital only" lenses not only are not smaller and lighter by any significant amount, THEY ARE ACTUALLY LARGER AND HEAVIER than some comparable 24 x 36 format lenses. Certainly there is NOT sufficient downsizing of size OR weight to justify LOSING 58% OF YOUR ORIGINAL IMAGE SIZE! However, once again defenders of the compromise "crop cameras" tout this non-existent "advantage." You've been sold a bill of goods again!

THIRD, the "size doesn't matter, only image quality matters" argument. This I'm sorry to say is self-contradictory. LARGER FORMAT PHOTOS HAVE SUPERIOR IMAGE QUALITY TO SMALLER FORMAT PHOTOS, BECAUSE LESS ENLARGEMENT (MAGNIFICATION) IS REQUIRED TO PRODUCE ANY GIVEN PRINT SIZE. This is why large format is better than medium format, medium format is better than 35mm, 35mm is better than APS, and APS is better than 110. THIS WILL NOT CHANGE REGARDLESS OF TECHNOLOGY ADVANCES, since any such advances will be applied to sensor chips of both formats. Further, Full Frame sensor chips can reduce pixel density and thus noise as compared with APS-C sensor chips while maintaining superior image quality. Even at equivalent pixel density, Full Frame provides less amplification of existing noise (again, due to reduced magnification) and thus superior IQ. (It's the same reason thumbnail sensors with similar megapixels produce inferior IQ as compared with the larger sensors in dSLRs.)

FOURTH, the "file size is too big" non-issue. Memory has gotten amazingly cheap and amazingly compact. Buffer sizes, etc. can be increased as necessary to accommodate ever larger files without any problem (20+ megapixel cameras already offer 5fps, which is more than adequate for ANY photographer; until late in the film-only years, 5 fps was the most you got with motor drives even on "professional" cameras). Technology will continue to enable faster processing and greater storage, so this is a meaningless "issue."

In short, APS-C offers NO operational advantages, NO appreciable size/weight advantages, and inferior IQ. The ONLY "advantage" about APS-C is that it is CHEAPER. And as the old saying goes, "you get what you pay for." So please, stop rationalizing about APS-C format as being a replacement for 24 x 36. It's not. Rather, it's just a stop-gap whose coffin is (albeit, slowly) being constructed as Full Frame inexorably becomes more mainstream (which will bring prices down). Full Frame is the future, and Pentax needs to get with the program. Once it becomes more affordable (and it will, because that is the nature of technological advance), nobody in their right mind will want a camera of similar size and weight in a smaller image format, because aside from cost differential there is NO BENEFIT (highly successful marketing BS notwithstanding lol).

Very cogent and logical arguments in favor of full frame. I knew of most advantages, but I for one had no idea that the "benefit" of the lens multiplication factor of APS-C over FF is bunk. Also very interesting to see real numbers showing that FF lenses do not have to weigh more than their APS-C counterparts. Bravo!

[regken]

In short, APS-C offers NO operational advantages, NO appreciable size/weight advantages, and inferior IQ. The ONLY "advantage" about APS-C is that it is CHEAPER. And as the old saying goes, "you get what you pay for." So please, stop rationalizing about APS-C format as being a replacement for 24 x 36. It's not. Rather, it's just a stop-gap whose coffin is (albeit, slowly) being constructed as Full Frame inexorably becomes more mainstream (which will bring prices down). Full Frame is the future, and Pentax needs to get with the program. Once it becomes more affordable (and it will, because that is the nature of technological advance), nobody in their right mind will want a camera of similar size and weight in a smaller image format, because aside from cost differential there is NO BENEFIT (highly successful marketing BS notwithstanding lol).

You are of course right. The only lenses I own are FF because there will be a move to the larger sensor. My lenses, for the most part, are no larger than DA lenses. The problem I see is body size. Presently I'm thinking about buying a 4/3eds body and using my FF Pentax lenses on it only because of body size. It would be used as a supplement travel body to my K10D. The K10D is as big as I personally want to go.

The sweet spot for body price seems to be around the $1,000 mark for both first time buyers and upgrade customers. Every time a body is offered with better IQ and priced below $1,000, I'll trade up as long as the footprint is no larger than the K10D. It doesn't matter if this better performance comes from advanced technology or increase in sensor size. I expect to own a FF 28MP ISO 12,800 K mount body the size of my K10D from some manufacturer that costs less than $1,000 in the future. It may take 3 or 4 upgrades to get there and maybe a switch to some other manufacturer, but as you say it is inevitable.

regards,

Ken

[Finn]

The only reason I would go for a 24x36 sensor is the viewfinder. I hate trying to focus manually while staring down a long, dark tunnel.

[Andrew Faires]

**snip**
FIRST, the much-worshipped "telephoto advantage:" This one is pure agricultural commodity (read: BS) cooked up by camera maker marketing departments and swallowed hook, line and sinker by many who are going a long way towards proving P.T. Barnum right. The focal length of a lens does NOT increase when you put it on a smaller format camera. The magnification of a lens does NOT increase when you put it on a smaller format camera. You do NOT NEED A LONGER FOCAL LENGTH LENS ON A FULL FRAME CAMERA TO TAKE THE SAME PICTURE WITH THE SAME MAGNIFICATION AS YOU CAN TAKE ON A SMALLER FORMAT CAMERA - all you need to do to get the EXACT SAME picture on a Full Frame camera is CROP the Full Frame picture down to the size of the smaller format. You DO NOT GAIN A THING - YOU ONLY LOSE SOMETHING - 58% of your image size.

SECOND, the supposed "size/weight reduction" of (in particular) "digital only" lenses designed to cover a smaller image circle rather than the full 24 x 36 frame. More agricultural commodity! Let's see how the specs of the two new "digital only" tele primes recently announced compare with their predecessors:

DA* 200 F 2.8 - 83mm wide x 134 mm long; 825 grams
FA 200 F 2.8 - 83mm wide x 134mm long; 785 grams
A 200 F 2.8 - 91mm wide x 138mm long; 850 grams

DA* 300 F 4.0 - 83mm wide x 184mm long; 1,070 grams
FA 300 F 4.5 - 73mm wide x 160mm long; 935 grams (no F 4.0 available)
A 300 F 4.0 - 84mm wide x 132mm long; 850 grams

The APS-C "digital only" lenses not only are not smaller and lighter by any significant amount, THEY ARE ACTUALLY LARGER AND HEAVIER than some comparable 24 x 36 format lenses. Certainly there is NOT sufficient downsizing of size OR weight to justify LOSING 58% OF YOUR ORIGINAL IMAGE SIZE! However, once again defenders of the compromise "crop cameras" tout this non-existent "advantage." You've been sold a bill of goods again!

THIRD, the "size doesn't matter, only image quality matters" argument. This I'm sorry to say is self-contradictory. LARGER FORMAT PHOTOS HAVE SUPERIOR IMAGE QUALITY TO SMALLER FORMAT PHOTOS, BECAUSE LESS ENLARGEMENT (MAGNIFICATION) IS REQUIRED TO PRODUCE ANY GIVEN PRINT SIZE. This is why large format is better than medium format, medium format is better than 35mm, 35mm is better than APS, and APS is better than 110. THIS WILL NOT CHANGE REGARDLESS OF TECHNOLOGY ADVANCES, since any such advances will be applied to sensor chips of both formats. Further, Full Frame sensor chips can reduce pixel density and thus noise as compared with APS-C sensor chips while maintaining superior image quality. Even at equivalent pixel density, Full Frame provides less amplification of existing noise (again, due to reduced magnification) and thus superior IQ. (It's the same reason thumbnail sensors with similar megapixels produce inferior IQ as compared with the larger sensors in dSLRs.)

FOURTH, the "file size is too big" non-issue. Memory has gotten amazingly cheap and amazingly compact. Buffer sizes, etc. can be increased as necessary to accommodate ever larger files without any problem (20+ megapixel cameras already offer 5fps, which is more than adequate for ANY photographer; until late in the film-only years, 5 fps was the most you got with motor drives even on "professional" cameras). Technology will continue to enable faster processing and greater storage, so this is a meaningless "issue."

In short, APS-C offers NO operational advantages, NO appreciable size/weight advantages, and inferior IQ. The ONLY "advantage" about APS-C is that it is CHEAPER. And as the old saying goes, "you get what you pay for." So please, stop rationalizing about APS-C format as being a replacement for 24 x 36. It's not. Rather, it's just a stop-gap whose coffin is (albeit, slowly) being constructed as Full Frame inexorably becomes more mainstream (which will bring prices down). Full Frame is the future, and Pentax needs to get with the program. Once it becomes more affordable (and it will, because that is the nature of technological advance), nobody in their right mind will want a camera of similar size and weight in a smaller image format, because aside from cost differential there is NO BENEFIT (highly successful marketing BS notwithstanding lol).

Just to add to this, even if you consider a reduced sized sensor as an advantage on the telephoto end, you're going to end up paying dearly on the wide end (ie, your 24mm lens just went from ultra-wide angle of view to a moderately wide angle of view).

As for size, the only advantage you'd get from APS-C in size-reduction is in the camera body itself as it requires less room to house the smaller sensor....and not by much as the lens would still have to maintain it's distance from the sensor (ie, the camera won't get any thinner, regardless of how small the sensor is - it might get marginally shorter though ).

Personally, I've got no complaints about image quality with the aps-c sized sensors. That said, one of two things happens when Pentax goes to a larger format: They keep the same pixel density and we get more resolution (and as you pointed out, don't need to enlarge as much to get the same sized print), or they reduce pixel density and we get better noise/dynamic range. Either way, it's a win/win scenario.

As for my predictions on the whole 'FF in the future scenario', I don't think Pentax will leap into the 24x36mm sensor fray. I've got no doubts that they'll go bigger, but I don't think they'll go past APS-H because they've got very few lenses in their current line-up that will cover anything beyond APS-H (and in some cases, APS-H would be a stretch). Hopefully I'm wrong though.

Like I said, I don't mind what I'm getting out of my camera/lenses right now. I'd like to see an improvement in performance before I see a bigger sensor.