[Kunzite]

1. It has been stated here, and in other forums, that the diameter of the K-mount restricts the amount of shift that a full frame sensor can have without moving the sensor beyond the image circle of current full frame lenses.
2. The K-mount is substantially a "Mechanical" mount. The electronics are there to describe the lens, and the working and range of apertures and the distance. Canon has a full electronic mount, and most other modern mounts are electronic. Maybe Pentax wants to move to a full electronic mount.
3. There is a possibility in Pentax's "think different' attitude and the desire to play in niche markets where the competition is less cut throat, that Pentax may opt for a Mirrorless full frame mount. They have experimented with this with the K-01 and have probably learned a lot of lessons. A different mount with a shorter registration distance would allow the use of an adapter with appropriate contacts to accept Pentax Full frame and APS-C lenses. See the Micro 4/3 and Canon EOS-M mount adapters.

1. It has been stated, but it's false. Sony could do it, why not Pentax?
2. The K-mount is using digital communication even from film era. I think even the aperture lever could be replaced, while not breaking backwards compatibility (the reason to do that would be video).
3. Think different by emulating MILC makers?
The MILC market is not niche, and it's highly competitive; even worse, it's more price-sensitive than the DSLR market (and that means, lower margins)

[EchoOscar]

I agree with EchoOscar here, I wouldn't find it insane that Pentax comes with a new mount and at the same time is able to provide some kind of backward compatibility with the K-mount. Thus everybody would be happy.

Also, maybe they are thinking about new technologies like this one :

The Q may well be Pentax's test laboratory for the coming mirrorless systems, along with the K-01.

I think that the mechanical shutter found in every dSLR and even in most MILC's today is one of the last remiscers of film camera technology to disappear, when the native digital cameras mature. I tend to think that all the mirrorless cameras in the near future will have none, and the job of the shutter is being done by a electronic one. Many mirrorless bodies already use electronic first curtains. It's only a matter of time that the mechanical shutter will be replaced with something simpler.

I'm not saying that's either good or bad, it's just something likely to happen, a logical progression within the technology. I happen to like the good ol' dSLR tech, be it a film or digital camera. I just hope they come up with better CMOS sensors in the near future, too.

Fixed it for you.

Quite. That was indeed an important fix. That single word was essential in delivering the point I was trying to make with the whole message. That little tiddy is quite critical for the future Pentax camera designs, mirrorless or dSLR, isn't it. Thanks.

[Anvh]

I think that the mechanical shutter found in every dSLR and even in most MILC's today is one of the last remiscers of film camera technology to disappear,

They will most likely be replaced in a few years i hope with LCD shutter.

[LamyTax]

How many these days do have FF pentax glass?
I don't except the DFA 100mm.

I have more than ten "new" FF-compatible lenses which I bought in the last ten years. Not counting the older stuff.
Pretty much everthing 50mm or longer works well on FF (budget lenses, some zooms are the main exceptions).
So, there's that. The DA 300/4 isn't half bad, btw.

[Gray]

It has been stated here, and in other forums, that the diameter of the K-mount restricts the amount of shift that a full frame sensor can have without moving the sensor beyond the image circle of current full frame lenses.

I don't think so... according to Falk Lumo 35mm Pentax lenses and Pentax FF SR will be compatible in the existing K-mount:

at f=50mm and t=1/5s the shake is 10/1000/s * 1/5 s * 50mm= 0.1mm.

The amount of additional image circle for shake reduction is not realistically estimated by most people. It's almost nothing.

It is larger for extreme tele lenses (the Pentax SR is made for up to 800mm focal length) because you always have to add about 25ms (1/40s) extra time for SR initialization and curtain travel times. And a bad shake requires 2-3x the amount of shift. Combine all this and you require 1.2mm. A value Pentax conservatively rounded up to 2mm.

However, extreme tele lenses have huge image circles. There is no real difference between an 35mm and an MF 600mm lens.

So, the entire SR discussion has zero impact on any FF discussion. Except maybe that it increases the engineering effort required to implant an FF sensor. As unlike shutter, prism and mirror, it is a first. BTW, you need a shutter with slightly larger opening too. So, you probably can't simply reuse your old 35mm shutter ...

Link

[Anvh]

I have more than ten "new" FF-compatible lenses which I bought in the last ten years. Not counting the older stuff.
Pretty much everthing 50mm or longer works well on FF (budget lenses, some zooms are the main exceptions).
So, there's that. The DA 300/4 isn't half bad, btw.

You mean the DA lenses that have a larger image circle then APS-C?
Yeah some might work but most vignetting but no matter how you turn it Pentax does not officially support it and there is the end of story.
No one knows how they might support DA lenses on FF camera, most likely they do it like Nikon and crop the image.

[ElJamoquio]

You mean the DA lenses that have a larger image circle then APS-C?
Yeah some might work but most vignetting but no matter how you turn it Pentax does not officially support it and there is the end of story.
No one knows how they might support DA lenses on FF camera, most likely they do it like Nikon and crop the image.

On Nikon you can choose whether to auto-crop or not. So if it's like Nikon, we're golden with our APS-C lenses.

[Anvh]

that's indeed great, first see if they make a 135 camera

[LamyTax]

You mean the DA lenses that have a larger image circle then APS-C?
Yeah some might work but most vignetting but no matter how you turn it Pentax does not officially support it and there is the end of story.
No one knows how they might support DA lenses on FF camera, most likely they do it like Nikon and crop the image.

No, I mean the DA-lenses that were specifically designed for FF.

[boriscleto]

No, I mean the DA-lenses that were specifically designed for FF.

There aren't any DA-lenses specifically designed for FF, there are D FA lenses...

That some DA lenses have an image circle large enough to cover an non-stabilized FF sensor is purely coincidental.

[LamyTax]

There aren't any DA-lenses specifically designed for FF, there are D FA lenses...

That some DA lenses have an image circle large enough to cover an non-stabilized FF sensor is purely coincidental.

Yes, yes... coincidence in the way even the patent says so?

[boriscleto]

Yes, yes... coincidence in the way even the patent says so?

You mean the DA* 60-250? It doesn't cover FF...

[LamyTax]

You mean the DA* 60-250? It doesn't cover FF...

Why would I mean a lens that doesn't even cover FF.

There's a thread or two in this forum... anyway, I actually still do shoot film. So, there's that.

[Anvh]

Why would I mean a lens that doesn't even cover FF.

There's a thread or two in this forum... anyway, I actually still do shoot film. So, there's that.

Because the aptent of the DA*60-350 actually says it cover FF.

[Anvh]

whoo some mistkes there.
it's called a patent and the lens is the DA*60-250