[cbaytan]

It just occurred to me most people (including me) keep defining a desire for an FF. FF means 24x36mm sensor, why limit photographers with this size of sensor? What if a phenomenal sensor comes little bigger in it's size (but still smaller than 645D's), What would happen?

Imagine a SLR with a littler bigger than 24x36 sensor, but body size is certainly a dSLR body and look, with an average FF camera price, how'bout on the lens side? All 645 lenses would cover this imaginary sensor too. So no problem in any sense.

Wondering if Pentax thinks the same things with me, as seemed today Pentax roads only on APS-C and medium format camera.

But this brings also three new questions to me .

1-Are 645 lenses too heavy and big to carry on a regular DSLR?
2-What is the maximum image diameter of the 645 lenses in case 645D sensor goes bigger in the future.
3-Am I thinking too absurd or too futuristic?

[Mikheil88]

I guess if that idea was good one, someone else in Pentax, Canikon or other manufacturer would think the same

Besides, I think there are certain circumstances that cause camera with large sensor be larger physically too. Look at this:


Left one is APS-C one, right - FF camera. As you see, smaller sensor can work with FF lens, so that would also apply in case of FF working with "645" lens, but I'm sure there will be some restrictions.

[Rondec]

The reasons to get full frame do seem to be getting fewer over time. High iso will always be better on full frame as compared to crop frame, but with how good APS C is getting, I don't think that is a huge reason any more. The other two things that are commonly stated are to get a larger viewfinder and to be able to better control depth of field.

I am not sure if you are wanting a third lens mount with a size between the current K mount and the 645 mount? The 645D is a crop frame camera as well. The sensor is between the size of full frame film and medium format film size. The sensor in the 645D is 44 by 33mm in size. Anyway, those that clamor the most for full frame really do so because they have spent a lot of money on full frame compatible lenses and they want to be able to use them as such, without a crop factor.

[Ash]

What makes sense about a standard FF dSLR is that many current K-mount lenses would be directly useable and don't need an adapter like a 645 lens would. It would be a good investment for the future to have a 'pro' option in a FF camera - but this continues to be a bone of contention; it's not much of a priority for Pentax apparently.

[cbaytan]

What I meant was the an FF-ish dSLR size camera (sensor size slightly bigger or smaller), with 645 mount, if crop factor would be big like >1.5 a new super wide angle zoom and/or a prime 645 lens would solve the lens line-up problem, if it doesn't exist yet. Just like a 645D with a certain crop factor, in a dSLR body. Only problem here is dumping all 35mm FF lenses and using only 645 lenses on all FF and MF cameras. APS-C cameras still can enjoy 35mm FF lenses.

This combination would be more functional than the strict 24x36 FF camera wouldn't it? All the 645 lenses you have you can use on either FF and MF cameras.

[jogiba]

Imagine a SLR with a littler bigger than 24x36 sensor

Why, I have a myriad of FF K mount lenses that would work perfect with a 24x36mm sensor K mount body and have no desire for a $10,000 645D body that does not even work right with 645 film lenses because the sensor is smaller. Go get a Leica S2 if that is what you want .
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[Lowell Goudge]

It just occurred to me most people (including me) keep defining a desire for an FF. FF means 24x36mm sensor, why limit photographers with this size of sensor? What if a phenomenal sensor comes little bigger in it's size (but still smaller than 645D's), What would happen?

Imagine a SLR with a littler bigger than 24x36 sensor, but body size is certainly a dSLR body and look, with an average FF camera price, how'bout on the lens side? All 645 lenses would cover this imaginary sensor too. So no problem in any sense.

Wondering if Pentax thinks the same things with me, as seemed today Pentax roads only on APS-C and medium format camera.

But this brings also three new questions to me .

1-Are 645 lenses too heavy and big to carry on a regular DSLR?
2-What is the maximum image diameter of the 645 lenses in case 645D sensor goes bigger in the future.
3-Am I thinking too absurd or too futuristic?

A couple of points here, with respect to the general questions.

Full frame can't really go beyond 24x36 because there are no lenses designed today for 35mm film cameras to project to a larger image circle. we have had 50 years of development where full frame was 24x36 and everything is dimensioned in a camera around that image circle, including the shutters, mirror boxes mirrors, and even the system regestry. (distance from lens mount to focal plane. to go bigger would be starting from scratch.

as for big and heavy, when you look at hanging a 70-200F2.8 zoom and a 2x TC on a camera today, that is pretty big and heavy. Yes 645 lenses (or 6x7 lenses are bigger and heavier, but that is driven by the image circle, up to a point they would not be too bad, but there would be tons of complaints. the present 35mm format is a workable format largely because of the camera size.

as for 645 lenses if the frame gets bigger, I have to ask bigger than what. a 645D has a small sensor compared to the 6cm x 4.5cm frame that the 645 film camera took, so there is pleanty of room for sensor growth before the 645 lenses become obsolete.

I think you are thinking absured personally.

[Digitalis]

6x7 lenses are bigger and heavier,

I own a few 4X5 and 8X10 lenses that are lighter than their 35mm equivalents. I think a lot of manufacturers go a bit overboard with their lens designs, though considering the limitations of the SLR design it is going to be pretty much inevitable that the lenses for a full frame 24X36mm sensor is going to be bigger, they pack so much resolution in such a small area, it is only recently with the advent of digital backs wehre Large format lenses have had to compete with 35mm glass and I have to say the current lines from rodenstock and Schneider are absolutely brilliant.

[RioRico]

we have had 50 years of development where full frame was 24x36 and everything is dimensioned in a camera around that image circle, including the shutters, mirror boxes mirrors, and even the system regestry.

Actually it's more like 80 years (for 35mm cams) or 75 years (for 35mm SLRs), but why quibble over a few decades? HF/APS-C size optics have been around for closer to 115 years. Practice, practice, practice...

I think a lot of manufacturers go a bit overboard with their lens designs...

Over at MFLenses.com is a discussion of 50's of wildly varying sizes. The MF is understandable. But in my own collection I'll compare the tiny Industar-50/3.5 and a midsize Meyer (Pentacon) Primotar-E 50/3.5, with a body the same size as the CZJ Tessar 50/2.8 or even the FA50/1.4. But the Meyer and Zeiss, with elements the same size as the Industar, are three times (3x) its size and weight. That bulk is cosmetic; those lenses *could* have been Industar-size pancakes. The difference: Wider bodies, deeper front insets. None dare call it ergonomics.

[paperbag846]

Well Pentax did exactly what you said... they skipped full frame and dropped a medium format digital (although, funny enough, the medium format digital is cropped from a true medium format, but still larger than FF).

I think FF is optimum for a pro, and ASP-C is really all you need as an enthusiast. Medium format is useful, but very very specialized. Many pros would never need the benefits, although some might desire them.

In the end, just like the 24 frames per second decision for film, 35mm is just the way things are and cameras will always be bound to those specifications. I could see myself buying full-frame one day, but not because I need it, and likely well after pentax is forced to offer one due to market pressures (E.g., if the D7000 was full frame at it's price, you can bet that the next flagship pentax would be fullframe too).

[cbaytan]

Imagine a SLR with a littler bigger than 24x36 sensor

Why, I have a myriad of FF K mount lenses that would work perfect with a 24x36mm sensor

Why? Because of more pixels, bigger S/N ratio, less pixel density, less noise, better IQ.
You can sell your FF lenses to get some 645 lenses.

[mysticcowboy]

All this angst over the lack of a FF Pentax. Hoya has given no indication that it will produce one. None of the recent Pentax lenses cover the full frame. It would take an incredible marketing push to convince pros to switch from their perfectly good Canikons. APS-C sensors are advancing in capability. The biggest growth in the field is seen in the EVIL format, which isn't conducive to large sensors. Other than pleasing a few malcontents on this forum, what incentive does Hoya have to produce a full frame camera?

[Lowell Goudge]

I own a few 4X5 and 8X10 lenses that are lighter than their 35mm equivalents. I think a lot of manufacturers go a bit overboard with their lens designs, though considering the limitations of the SLR design it is going to be pretty much inevitable that the lenses for a full frame 24X36mm sensor is going to be bigger, they pack so much resolution in such a small area, it is only recently with the advent of digital backs wehre Large format lenses have had to compete with 35mm glass and I have to say the current lines from rodenstock and Schneider are absolutely brilliant.

The fact is your 8x10 camera was with a bellows, and focusing rail, and did not have a focal plane shutter probably, The issue with a 35mm camera / lens system is the lens is burdoned with all the mechanical needs that a 4x5 or 8x10 lens is not. the same is true of MF SLRs, look at the 125mm lens for a 2x3 speed graphic and compare it with a 125mm lens for a 6x7. it is the camera design, specifically the reflex deesign and the need to have the lens big enough on its own to support the image circle and focusing helix, not a bellows with rack and pinion focusing, that makes them big and heavy.

Actually it's more like 80 years (for 35mm cams) or 75 years (for 35mm SLRs), but why quibble over a few decades? HF/APS-C size optics have been around for closer to 115 years. Practice, practice, practice...

OK so I am understating the age of 25mm as the most popular format

Over at MFLenses.com is a discussion of 50's of wildly varying sizes. The MF is understandable. But in my own collection I'll compare the tiny Industar-50/3.5 and a midsize Meyer (Pentacon) Primotar-E 50/3.5, with a body the same size as the CZJ Tessar 50/2.8 or even the FA50/1.4. But the Meyer and Zeiss, with elements the same size as the Industar, are three times (3x) its size and weight. That bulk is cosmetic; those lenses *could* have been Industar-size pancakes. The difference: Wider bodies, deeper front insets. None dare call it ergonomics.

there is some of that, when you look at any lens at any focal length, they are bound by the size of the mount and the need to put the focusing and aperture controls some where.

but the point remains, go back to the OP's question, why not a 35mm "like" camera but perhaps bigger than 24 x 36mm frame, Because thtere are not a lot of lenses to support it that's why.

as for bigger MF SLR sensors, as I said, plenty of room left in a 645 box to put a bigger chip.

[noahpurdy]

What makes sense about a standard FF dSLR is that many current K-mount lenses would be directly useable and don't need an adapter like a 645 lens would. It would be a good investment for the future to have a 'pro' option in a FF camera - but this continues to be a bone of contention; it's not much of a priority for Pentax apparently.

But what doesn't make sense about the idea of a Pentax FF dSLR is the current lens line-up (Also the fact that none of the legacy lenses are corrected, or optimized for use with a digital sensor).

Looking at the current line-up should tell you that a FF Pentax isn't coming, and won't be coming; for example look at all the DA* series if the lenses were the lenses they appear as with the crop factor applied:

24-70mm f/2.8 (DA* 16-50mm)
70-200mm f/2.8 (DA* 50-135mm)
90-375mm f/4 (DA* 60-250)
82mm f/1.4 (DA* 55mm)
300mm f/2.8 (DA* 200mm)
450mm f/4 (DA* 300)

That's a pretty solid line-up and apart from a wide-angle prime or peeping-Tom telephoto there aren't many gaps. (It's especially solid when you look at just how niche of a company Pentax is.)

I would argue that with improving sensor technology Pentax has no justification for a FF dSLR, as I predict that in no more than two years time there will be negligible difference in IQ between the two.

[Lowell Goudge]

But what doesn't make sense about the idea of a Pentax FF dSLR is the current lens line-up (Also the fact that none of the legacy lenses are corrected, or optimized for use with a digital sensor).

Looking at the current line-up should tell you that a FF Pentax isn't coming, and won't be coming; for example look at all the DA* series if the lenses were the lenses they appear as with the crop factor applied:

24-70mm f/2.8 (DA* 16-50mm)
70-200mm f/2.8 (DA* 50-135mm)
90-375mm f/4 (DA* 60-250)
82mm f/1.4 (DA* 55mm)
300mm f/2.8 (DA* 200mm)
450mm f/4 (DA* 300)

That's a pretty solid line-up and apart from a wide-angle prime or peeping-Tom telephoto there aren't many gaps. (It's especially solid when you look at just how niche of a company Pentax is.)

I would argue that with improving sensor technology Pentax has no justification for a FF dSLR, as I predict that in no more than two years time there will be negligible difference in IQ between the two.

explain what is wrong with legacy glass with respect to digital sensor for me.

With the exception of the first generation sensors, all sensors today have micro lenses that are much better at capturing light at other than perpendicular angles, therefore the issue with vignetting due to non perpendicular light at the edges is gone.

I have only one lens that suffered from sensor reflection and that had nothing to do with coating the rear element but with a shiny part inside the lens. and it was a cheap lens any way.

so the legacy glass is a good option, BUT, you are correct, pentax has steadfastly maintained it is comitted to ASP-C format, and I am sure if you look at the ratio of FF to ASP-C cameras there is no room for a 4th player beside nikon canon and sony. Also note that sony is not going to sell any more ff sensors to nikon, which is why their last ff was released 2 years ago. The market is just too small for pentax to crack and make money. I am sure the canon and nikon FF users are really getting subsidized by the ASP-C bodies and the marketing budget already.

You have to remember selling a FF is not like dressing up a base ford and making a lincoln, where all the internal parts are the same and only the skin changes, it is more like comparing a chevette to a corvette. Or if I stay with the ford analogy, a ford focus and a GT40