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03-22-2015, 10:42 PM   #16
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QuoteOriginally posted by ndevlin Quote
.

None of the tolerances in the 67 are digital-viable. To say nothing of the shutter vibrations. Let's build a whole camera body from the ground up. Something Phase One has proven utterly incapable of doing....in mere 645.


- N.
Mirrorless? Build the "new" P67 body from the old one with tighter tolerances. Probably what Pentax did with the film 645 bodies. Sony would have to come up with a cropped sensor version of the 67 format.

03-24-2015, 10:58 AM   #17
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There exist two possibilities for producing large sensors, either scale the process, or use tiling, but both have hurdles. Sensors are made by etching silicon with a laser focused through a mask of the transistors and/or pixels, layer-by-layer. The detail with which it's possible to reproduce the mask detail on silicon is measured in nanometers and the smaller the details, the more stuff you can cram in, which is how Sony sensors manage to achieve low read noise through small process manufacture - the circuitry for the pixel readout is situated directly next to the pixels they read.

If you can imagine this process as a projector throwing an image on a large screen, the resolution of the projector, whether it be 720p, 1080p or 4K, doesn't limit how large the projected image can be, but you clearly get less detail per unit of measure as you scale up. Even if you could project a sensor mask onto a piece of silicon 6 x 7cm large, the detail level per pixel probably wouldn't allow for the design to work from an electrical standpoint, or just wouldn't perform very well. A small start-up called LargeSense is working on an 8x10 digital camera, but the sensor is only 12MP and has a base ISO of 2100, no doubt due to a very large production process.

Tiling smaller chunks is a technique that has been successfully used for a long while now, but introduces problems when slight variances between chunks show up when you push the exposure, and it's not exactly inexpensive to do either. The chances of getting a sensor even close to the size of an entire wafer without defects is extraordinarily low, so the price of each "pristine" chunk is very high. Such chunks do exist, but they are more often than not sourced to the medical, aerospace and scientific industries; there are probably few enough to go around as it is even within those sectors.
03-24-2015, 12:25 PM   #18
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stick a dang scanner on it and you've got yourself a digital 67

or just shoot film and scan it. or shoot film and have it scanned. a roll of slide film purchased and sent away for processing and scanning is about $30 vs the second mortgage you'd have to take out to afford a 67 format sensor of any type

you can also make your own 6x7 sensor
03-25-2015, 02:22 AM   #19
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Exactly what I wanted to say: Make it a scanning (2d) Sensor that is 6cm wide. Then you can shoot 6x4,5, 6x6, 6x7 :-)
Flash sync speed would be ... not so good I guess...

Just kidding...

03-25-2015, 06:18 AM   #20
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QuoteOriginally posted by Simen1 Quote
Loads of money yes, but i was thinking technical requirements and barriers. CMOS sensors just recently jumped

If Pentax made a real non cropped 67D it would be the mother of all medium format cameras. Shaking the whole medium format industry, making jaws drop. It wont be a big seller but the Pentax brand may get the respect they truly deserve and sell a few to very rich pepole.

So what do you think?
Pure fantasy. Easy to explain.
1. The demand of photo market for such camera, sensor and lenses are close to ZERO.
2. 67 lenses are discontinued. To make new AF 67 mount has no any sense.How many photographer would be able to buy such system?
3. The development cost and cost of such sensor and lenses would be very high.
4. There are adaptors to use 67 lenses on 645 cameras.
5. The reserve of 645 sensors potential is very high. It's easy to put more than 100-150 MP to 56*41.5 mm sensor.
But nobody made such sensors (MP and size) before, because no serious demands of market. There is sensor close to 56*41.5 mm, but a bit smaller (53,9x40,4 mm).
6. There are industrial and special sensors with high MP for special demands.
03-27-2015, 03:08 AM - 1 Like   #21
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QuoteOriginally posted by Simen1 Quote
Loads of money yes, but i was thinking technical requirements and barriers. CMOS sensors just recently jumped up from 24*36 to 33*44 mm (cropped 645) so i guess that non cropped 67 CMOS is out of reach for at least a decade*. But Is there any really large single CCDs out there? For custom buildt astronomy purposes or something? Or maby a gapless mosaic of smaller sensors? If its going to have very many of megapixels on a single die it might have a higher tolerance of stuck pixels to give decent yields. Readout speed might be a challange. It should be able to shoot again within a couple of seconds, but A/D should be at least 14 bit.

*A Sony representative said in an intervju that the biggest challange of making their 51 Mp medium format CMOS sensor was to stitch masks for the pixel array over such a large area with enough precicion to avoid yield problems. Aperently its a repeating task where small misalignments can get bigger with every tile of pattern that is made.

Also a few big things had to be changed from the 67II. Introduce electronic contacts in the mount for communication with future 67 lenses. But they should make it compatible with existing lenses too. A really good live view screen with digital focus peaking on screen would help on the lack of AF. The mirror and viewfinder may be sacrificed for a lighter camera and for avoiding mirror shaking.

If Pentax made a real non cropped 67D it would be the mother of all medium format cameras. Shaking the whole medium format industry, making jaws drop. It wont be a big seller but the Pentax brand may get the respect they truly deserve and sell a few to very rich pepole.

So what do you think?

if pentax made a un-cropped 645 sensor, it would be the mother of medium format cameras.
03-27-2015, 03:31 AM   #22
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QuoteOriginally posted by ndevlin Quote
This is a fun 'over beers' discussions, which I do not mean to dampen, but the reality is this won't happen, really ever.
I'm inclined to agree, but in 15~35 years from now it might be a possibility. Assuming still photography as we know it still exists.

QuoteOriginally posted by ndevlin Quote
Let's build a whole camera body from the ground up. Something Phase One has proven utterly incapable of doing....in mere 645.
Both of us know that is basically a mamiya 645AFD in phase one drag. To be honest I never liked mamiya medium format SLRs, there was always some little operational quirk that could total an entire shoot. A colleague of mine said: you always have to have a back up body(or better yet, two) when you worked with mamiya.

Leica did a good job of building the S2* , Hasselblad have been using the same basic chassis for their H and V series cameras over the past 50 years and it hasn't hurt them significantly. however, don't get me started on all the things that are wrong with the Hy6.

QuoteOriginally posted by ndevlin Quote
But it IS fun to dream. For me, that looks more like a digital Mamiya 6
Out of curiosity, why the Mamiya 6** not the 7II? Apart from the lenses (which have a crippling issue with the electronics) I thought that camera was well built.

* To be completely honest I'm still a bit surprised that Leica made the S2 an SLR, ( the S1 was a 36mmX36mm format mirrorless, but that was a necessity as it used a scanning back as I recall) Leica should have made the S2 mirrorless and it possibly would have enjoyed a broader market appeal and have been more successful. To my hands the the S2 feels like an overgrown R, not that there is anything inherently wrong with that it just feels like territory Leica has crossed before.
** I presume you are referring to the newer Mamiya 6 and not the old Mamiya 6. For a moment there I was perplexed: why would anyone want that, though I can imagine hipster photographers would would just love it.


---------- Post added 03-27-15 at 09:19 PM ----------

QuoteOriginally posted by bull drinkwater Quote
if pentax made a un-cropped 645 sensor, it would be the mother of medium format cameras.
The downside to that would be that most of the new D-FA 645 lenses would have to be re-designed to cover the larger sensor. That would tick a lot of people off.

Last edited by Digitalis; 03-27-2015 at 04:56 AM.
03-28-2015, 04:14 PM   #23
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Let's see... $100k for the camera, or covering a lifetime of film developing costs. Heck, for that investment I bet you could run a lab on the side and it would net to zero...

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