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Blackmagic Pocket Cinema Camera 4K

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3 hours ago, John Brawley said:

I don’t think it ever even got made, let alone sold.  I think they only announced it.

It’s worth reading the very interesting article Andrew posted about how Nikon sensors get made..I would hope it may change our view of the idiotic phrase “off the shelf sensor”.... because no sensor is off the shelf....

JB

I think may have misinterpreted something because that article doesn't dispute anything about off-the-shelf sensors. That whole article was about Nikon makes there own custom sensors and has nothing to do with purchasing sensors made by other companies.

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1 minute ago, Myownfriend said:

I think may have misinterpreted something because that article doesn't dispute anything about off-the-shelf sensors. That whole article was about Nikon makes there own custom sensors and has nothing to do with purchasing sensors made by other companies.

I see users of this an other forums often quoting the phrase "off the shelf sensor".  In a similar line of thinking, many have theorised that because Sony "make" a lot of Nikon's sensors, that they're essentially a Sony sensor in a Nikon camera body. Sony look, Sony tech and Sony DNA.  Much like the conversation in this very long thread about the source of the sensor in the namesake of the thread and it's DNA....

I suggest this article as a way of drawing parallels.  Sony make certainly fab the sensor but it's anything but a Sony.

JB

 

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Well yes, there's definitely things that companies can do to make the image from an off-the-shelf sensors look unique to the camera but if they're using a Sony sensor, it's very much an unmodified Sony sensor. To my understanding, working with an OTS sensor is similar to working with the SOC in the Raspberry Pi. You can overclock different parts of it's chip, cool it differently, and try to get it to output custom resolutions but that's not the same as customizing the chip. 

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The best part of that whole article is the Comment section on the Nikon Sensor stuff.  And mostly from a person named ZR. Seems like a lot of all the senor stuff Ain't really as new as we think. Physics and all.

https://www.imaging-resource.com/news/2018/07/17/pixels-for-geeks-a-peek-inside-nikons-super-secret-sensor-design-lab

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9 hours ago, John Brawley said:

I don’t think it ever even got made, let alone sold.  I think they only announced it.

I'm sure they must have at least made prototypes. 

 

Would be pretty darn crazy if they'd announced a camera without at least having one rough prototype first. 

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16 hours ago, IronFilm said:

This would have been true a couple of years ago or more, it made more sense to get a C100. 
But as "4K" gets wanted more and more, even on low end jobs, then there is a possibility the C100 might hold you back more in getting work than say even having a Panasonic GH4 would help you. Might wash out and be a coin flip as to which is better. 

Well it never got sold, for basically the same kind of reasons BMD had, the benefits of having global/rolling as an option wasn't worth it for the trade offs. 

 

The question is where they were sourcing a 5K dual-gain sensor from.  Blackmagic paid millions of dollars for Fairchild to develop the 4.6K sensor with switchable rolling/global shutter. Where did they find this sensor?  And furthermore, how were they able to successfully cool such a sensor in a really small body?  The camera would not have been announced if they did not have a working sensor and/or partly functioning prototype.

Obviously the camera was dropped, but from specs alone that camera was market-leading with switchable global/rolling shutter, high dynamic range, and  a small form factor.

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13 hours ago, John Brawley said:

I don’t think it ever even got made, let alone sold.  I think they only announced it.

It’s worth reading the very interesting article Andrew posted about how Nikon sensors get made..I would hope it may change our view of the idiotic phrase “off the shelf sensor”.... because no sensor is off the shelf....

JB

Of course there are... 

To quote Sony...

"The third category of sensors is completely generic – the sensors are created for use internally and to sell externally, to anybody. China or Taiwan or wherever.”

You can literally pick up a catalog of sensors from Sony, Samsung or Omnivision for that matter.

What Nikon does - getting a custom build with their design exclusive to them - is the 'exception' rather than the 'rule'

'Custom builds' are expensive to design and even more expensive to build because you both need a separate manufacturing line and you then have to ramp up to an acceptable yield.

If you consider that the cost of a generic M43 sensor is US$40-50 a piece and you expect to sell 100,000 cameras, your spend on sensors is roughly US$4.5m.

Most components in cameras are 'generic' or 'off the shelf'. Shutters by Nidal Copec, EVFs from Epson etc...

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53 minutes ago, Savannah Miller said:

And furthermore, how were they able to successfully cool such a sensor in a really small body? 

It's not that hard to cool a sensor in a small body.

The Canon XC10 has air cooling with fans, and it's a very compact body.  Here it is vs a 5D mkIII body:

1407973507_ScreenShot2018-08-05at1_42_52pm.thumb.png.7b6c1634948f988c0f1b0154fb4428e0.png

1177023852_ScreenShot2018-08-05at1_45_05pm.thumb.png.24aba7b29a4ba9f681bdac7e3c342dad.png

 

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Dual-gain sensor is a different type of sensor.  Blackmagic has refrained from making a pocket 4K for years because they could not find a sensor they could cool that also had good enough dynamic range.

Fairchild does not make a 5K sensor and I am not sure Kinefinity most likely did not pay for its development.  Who else sells these kind of sensors?

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27 minutes ago, Robert Collins said:

Of course there are... 

To quote Sony...

"The third category of sensors is completely generic – the sensors are created for use internally and to sell externally, to anybody. China or Taiwan or wherever.”

You can literally pick up a catalog of sensors from Sony, Samsung or Omnivision for that matter.

What Nikon does - getting a custom build with their design exclusive to them - is the 'exception' rather than the 'rule'

'Custom builds' are expensive to design and even more expensive to build because you both need a separate manufacturing line and you then have to ramp up to an acceptable yield.

If you consider that the cost of a generic M43 sensor is US$40-50 a piece and you expect to sell 100,000 cameras, your spend on sensors is roughly US$4.5m.

Most components in cameras are 'generic' or 'off the shelf'. Shutters by Nidal Copec, EVFs from Epson etc...

You're implying that you can buy a generic sensor, put it in a camera and you get a picture.

It's not that simple though.

Let's look at a camera that uses an off the shelf sensor in the sense you're describing.  The Apertus project.

Started conceptually in 2012.... https://www.apertus.org/

Still not really a production ready useable camera and they've been working on that for YEARS, even with the magic lantern help and the open source community.

In the time since they've started, the same sensor that has been developed into use for the AJA Cion, several BMD 4K cameras and other machine vision cameras.

If it really was off the shelf, then Apertus would have a camera that doesn't still have issues Apertus have.  They would have delivered by now with the significant effort going into it.

Why haven't they ?  Why haven't they just been able to plug the same off the shelf sensor used in other cameras into a body, program up some boards and get it working ?

Because there's no such thing as an off the shelf sensor.  Even the off the shelf sensors still need a huge amount of development to make them into a functional product that can ship.

It's certainly not the exception rather the rule at all.

JB

 

 

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24 minutes ago, John Brawley said:

Because there's no such thing as an off the shelf sensor.  Even the off the shelf sensors still need a huge amount of development to make them into a functional product that can ship.

JB

This is simply a non-sequitur. First of all there 'isnt' an off the shelf sensor. But then there 'is' but you need to add some tech to turn the sensor into a camera - 'no shxx sherlock!!'

But to explain my point. It is generally thought that the GH5S, BMPCC 4k and Z Cam 2e all use the same generic sensor.

The Sony IMX294CJK sensor (which is part of the Starvis line developed originally for security cams.)

Here are its specs....

https://www.sony-semicon.co.jp/products_en/IS/sensor0/img/product/cmos/IMX294CJK_Flyer.pdf

Now you might know that amongst those 3 cameras the Z Cam 2e is the only one to offer 4k 120fps. But if you read the 'sensor specs', you will see that 120fps 4k can only be achieved from a 10 bit signal...

And sure enough if we look at the Z cam 2e specs.... 120fps only comes from a 10 bit signal....

 

Clipboard Image (188).jpg

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5 hours ago, Robert Collins said:

This is simply a non-sequitur. First of all there 'isnt' an off the shelf sensor. But then there 'is' but you need to add some tech to turn the sensor into a camera - 'no shxx sherlock!!'

But to explain my point. It is generally thought that the GH5S, BMPCC 4k and Z Cam 2e all use the same generic sensor.

The Sony IMX294CJK sensor (which is part of the Starvis line developed originally for security cams.)

Here are its specs....

https://www.sony-semicon.co.jp/products_en/IS/sensor0/img/product/cmos/IMX294CJK_Flyer.pdf

Now you might know that amongst those 3 cameras the Z Cam 2e is the only one to offer 4k 120fps. But if you read the 'sensor specs', you will see that 120fps 4k can only be achieved from a 10 bit signal...

And sure enough if we look at the Z cam 2e specs.... 120fps only comes from a 10 bit signal....

 

Clipboard Image (188).jpg

Interesting point, I wonder if we're will see an update that will allow for 4K @120 fps 10 bit for the GH5S? That would be nice to see. 

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2 hours ago, DBounce said:

Interesting point, I wonder if we're will see an update that will allow for 4K @120 fps 10 bit for the GH5S? That would be nice to see. 

In order for the GH5s to do that, it would need to have the proper cooling for it and it would require that the HEVC/h.264 decoder can encode fast enough.

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Do we really and truely honestly all believe that the exact same sensor is being used in these cameras ? The X7, E2, GHx, P4k...

It’s a rhetorical question.  Which means I know the answer I’m just asking it here publicly...

And why does it even matter.  Even if they ARE the exact same sensor. Every camera manufacturer will get different results and we learn NOTHING from these kinds of theoretical sensor discussions. Look at the previously mentioned CIon / BMD 4K / Aperture images.  Are they the same ?  Look at digital Bolex, who used the KAF / KODAK senors.  Are they the same images as the Ikonoscope / Leica / Olympus E series cameras that also used the same sensor family ? 

Just because they share the same sensor or sensor linage or it comes form the same factory, it’s almost meaningless because the company making the images form that sensor have to do so much customising, calibrating and processing of the image, it becomes irrelevant other than the specs we already know...

Let’s just look at the pictures instead of obsessing over the specs....

JB 

 

 

 

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As much as two cameras with the same sensor doesn't indicate that the images will look the same, you can generally get an idea of what dynamic range is like.

Camera manufacturers aren't stupid these days and if there was a way to squeeze out more DR out of the sensor they'd likely all be using it. Color science is another issue entirely.

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16 minutes ago, Savannah Miller said:

you can generally get an idea of what dynamic range is like.

Disagree. The chips added by the camera manu determine how well the signal is processed: FPN removal and other denoising implementations determine how many usable stops a camera has.

camera =/= only sensor

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