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10-16-2015, 06:40 PM   #121
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QuoteOriginally posted by Kunzite Quote
The 645 to K-mount adapter was available for decades.
Autofocus and fully compatible? I do have the manual adapter and i have used my manual and autofocus 645 lenses with my k3 with great results but all in manual mode.

10-16-2015, 08:41 PM - 2 Likes   #122
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Oh come on (some of you) guys, it's fake.

Nobody with such a poor grasp of the English language as whoever put this together would be likely to know about the plural possessive apostrophe used in competitors' at the top. Nobody that is except a born English speaker trying to fake a Japanese speaker.

And no professional worth his salt would produce such an amateur looking slide, his or her departmental manager would be onto them in a flash, it's awful, simply awful - my 11 year old grand daughter could do better.

Fake.
10-16-2015, 08:45 PM   #123
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QuoteOriginally posted by Kunzite Quote
Sorry... there were some rust points so I decided to clean them and repaint the bridge before giving you the title. Unfortunately I'm out of paint, so please, do send more money


I'm afraid I have to ask you to prove that it can be done, instead of endlessly attempt to prove you that it can't - for every idea you (or someone else) might have


Oh, great. More conditions to satisfy in order to make it work.
In fact it's:
- having to use a fixed mirror (which will steal light from the imaging sensor, unless they manage to implement the variable transmission mirror idea).
- the 'pellicle' mirror might introduce defects in the resulting image (IIRC Sony SLTs had such issues).
- the fixed mirror frame would introduce mechanical vignetting, and a resign where you could easily remove the mirror (for cleaning the sensor) requires such a frame. And it puts restrictions on the mirror's size.
- no secondary mirror to send light to a dedicated AF system, which means no dedicated AF system. Bye-bye excellent low-light AF capabilities.
- viewfinder prism and everything around it moved forward, viewfinder optics extended
And it still won't be enough.
The camera could offer this feature in live view only with the mirror up. The camera would have to be on a tripod anyway. I don't see any of the issues you mention being insurmountable.

- Regarding the fixed mirror, they have a patent for that, which is different from the Sony implementation. Whether it is ready for introduction is another question, but it could be. I very much doubt they would go forward if it adversely impacted image quality. Note that it would have other benefits, like reducing mirror shock - a problem that makes it difficult to reach the potential of high-resolution sensors in some circumstances.
- The vignetting issue could be solved if the mirror were made big enough for whatever crop of the 645 lenses they can manage with the SR system. It doesn't have to be the whole frame to be useful.
- Many sensors have AF included now. Pentax AF is not generally perceived as being very good anyway, so they have less to lose from starting from the ground up with a sensor-based system. The other advantage of sensor-based AF is that is more accurate than even the best off-sensor systems, and that is becoming more important with high megapixel sensors. DPR keeps pointing that out and they are not the only ones.
- The VF on the mock-up of the Pentax FF does indeed look more prominent than other cameras. It could be that that there are differences to the mirror box area and VF itself.
- If using 645 lenses is indeed a major feature on this camera, it would make sense for Ricoh to make a new WR version of the adapter, so it would be "new".

I don't see anything unreasonable about the specs shown. Pentax and Ricoh have a history of using the sensor shift for interesting functions, and this seems in line with that history.

My own crazy idea, I was reading Ming Thein's article about tilt-shift lenses. Tilt shift 101 ? Ming Thein | Photographer Would it be possible for Ricoh to create a tilt-shift adapter to use 645 lenses on the FF? Perhaps it would require more space than the adapter would allow. The secondary question is whether it would be possible to create K-mount tilt-shift variants of existing 645 primes.
10-17-2015, 01:22 AM   #124
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Please do me a favor: take (preferably) an old film camera, a ruler and see for yourself what 44x33mm in a small format body actually means. I did that.

10-17-2015, 01:51 AM   #125
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And that would tell me what exactly? That a 44x33 sensor wouldn't fit in there? I'm well aware of that.

Pentax cameras already do composition adjustment by moving the sensor. All this would be was taking four shots at the corner positions and combining then into one image when the image circle of the lens allows. It clearly wouldn't cover the whole 44x33 size. It isn't a killer feature, but it would be useful for some people. They could even enable APS-C cameras to do the same with full frame lenses.

The problem is it would be difficult to frame because even live view would not show the whole image.
10-17-2015, 02:24 AM   #126
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As I already said, it must be some significant improvement over 36-42MP with Pixel Shift Resolution in order to make it worth the effort and cumbersomeness.

In my previous post I advised you to play around with the camera and a ruler, in order to see how little space is actually available. Now, I have to advise you to play with composition adjustment - the range of movement is quite small. Composition Adjustment is nothing more than a positioning fine-tuning function, so that's fine.
I estimate the area gained (K-5IIs, 35mm lens) by using Composition Adjustment mechanism in this way at about 20%. "Useful for some people"? I doubt that.
10-17-2015, 02:29 AM   #127
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As an APS-C to full frame tool, I can buy it - most high end digital SLRs are bigger than the smallest film SLRs anyway - but I agree now with those who are arguing that FF to MF is probably too much for the size of the camera. Unless the hypothetical 645-FF adapter is glassed. That's a possible workaround. Personally I wouldn't mind a glassed adapter to take FF lenses down to the APS-C circle either.
10-17-2015, 02:50 AM   #128
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APS-C to FF, with a much larger SR system - because the ~20% of the current one is nowhere near enough. Then, again, we'd have to start thinking about interference with the viewfinder components and so on; and an entire new SR system, designed for large movements, would need to be made.
Occam's Razor tells that Pentax would simply make us a FF camera.

645 to FF Metabones-like adapter could be possible, but I really don't think we'll see one. Pentax would rather have us buy 645Zs

K-mount FF to K-mount APS-C Metabones-like adapter is not possible. Only K-mount FF to short registration distance APS-C mirrorless. Pentax won't do it.

P.S. Perhaps another image would help:


10-17-2015, 02:53 AM   #129
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QuoteOriginally posted by pathdoc Quote
(...) Personally I wouldn't mind a glassed adapter to take FF lenses down to the APS-C circle either.
This is called a focal reducer and has the particularity to decrease the register of the lens (whereas a focal multiplier increases said register and allows for inserting the converter between lens and camera).Ttherefore, It can only be used with a body, the mount register of which is shorter than that of the lens used: MF lens on a 24x36/APS-C DSLR or DSLR lens on a mirrorless camera.
10-18-2015, 06:15 AM   #130
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Original Poster
Asahiman put the rumor out of it's misery.

QuoteOriginally posted by asahiman over at the hipsters who moved to Seattle place:
It's fake,for sure.
I have to every Pentax since K 10 the training,information and show files and PDF,nothing is looking like this stuff,also the Ricoh materials.
Looks like nonsense.
Best regards
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