New Blackmagic Camera July 16th?

Joshua Cadmium said:
I've been trying to figure out what it is about the footage from this camera that seems special. We've all seen higher resolution video downsized, extremely sharp lenses, etc., so I was trying to figure out what it is specifically about the sensor that is contributing to the uniqueness of the image. I believe I have it figured out.

This is the first time we have a pure black and white capture being used as the luma in a color image.

This sensor is not only 12K, it's also an 8.5K purely monochrome sensor.

We know from their patent that Blackmagic is using a checkerboard pattern for the clear sensor elements. So, those clear photosites are now in the same pattern that Green photosites would otherwise be on a Bayer pattern sensor.

So, the math to figure out the basic minimum luma resolution is the same as Bayer. This is an 79.6 megapixel sensor, so there are 39.8 megapixels worth of clear photosites, which is just about 8.5K. (8.5K 17:9 would be 8704x4608 which is 40.1 MP. 8K 17:9 is only 35.4 MP.)

This is huge. This sensor gives the benefits of both color and monochrome sensors.

All image subsampling that we use is based on the idea that the human brain responds to luma resolution more than chroma resolution. This is the first color sensor in a cinema camera that also gives us unfiltered luma - more of what we respond to.

Virtually all the digital color images, moving or not, that we have seen since the dawning of the technology have had their luminance filtered, mainly by green.

We are seeing a pure unfiltered luminance combined with a high chrominance for the first time and it looks special.

It's as if a giant green filter was removed from our field of view.

And 8.5K is the bare minimum of luma resolution. Since this is in a Bayer type pattern for luma, the same benefits should apply. Most people (including Graeme Nattress of Red: https://www.premiumbeat.com/blog/exclusive-interview-reds-sensors-resolution/) estimate the true luma resolution of Bayer to be 80% of the total resolution. If that held true for this, then we would be closer to a 9.6K monochrome sensor.

And, on top of all of this, the clear photosites are most likely capturing more chrominance resolution than a Bayer pattern would, because, as I posted earlier, you can use subtraction from the nearby photosites to work out the color that the clear photosite is capturing. If that is the case, chrominance resolution is increased because the clear photosite is contributing double or triple the color information than a filtered photosite would. And, in general, the filtered Red and Blue photosites are in a ratio to green that is 33% more than they would be on a Bayer pattern. The bottom line is that there should also be more chrominance resolution than there would be in an equivalent 12K Bayer.

This sensor is truly something special.
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Think of it in physical print making where there are inks of three colors plus one of black.
 
Joshua Cadmium said:
On top of the size of the photosites, the clear photosites have the ability to play a huge role in increasing the amount of chrominance data.

Very basically, pixels from Bayer look like this:

View attachment 139804


If you look inside the yellow lines, you can see that each pixel is capturing 1/4 of each of the surrounding photosites to make a total pixel. (And, incidentally also see why you need extra photosites outside of the pixel area.)

So, to determine exactly how much of each color we are capturing in total in this 6 pixel by 2 pixel area, we can simply add all the 1/4 portions up.

Green = 24 quarters or 6 total photosites (24/4)
Red = 12 quarters or 3 total photosites (12/4)
Blue = 12 quarters or 3 total photosites (12/4)

And this makes sense - we have 12 total pixels in this tiny area and we know that half the photosites would be Green (6 total) and one quarter would be red and blue (3 total for each).

Makes sense?

So, now let's look at the same size area on the Blackmagic sensor.

View attachment 139805


As I mentioned before, you can use the surrounding colors to subtract from white to determine the color information that the clear pixels are capturing. (You can, once again, read more info here: http://image-sensors-world.blogspot.com/2013/07/aptina-explains-clarity-technology.html)

Looking at the above image, you can see that the white photosites border two other colors, and you could subtract the two colors from white to get the third color.

So, for instance, in the first pixel, the corners of the white photosites that meet the corners of the green and blue photosites could become 1/4 red photosites by subtracting green and blue from it. (And I kept a white border around those 1/4 portions of calculated color to help distinguish them.)

In this case, if we added up the 1/4 portions we get this:

Green = 16 quarters or 4 total photosites (16/4)
Red = 16 quarters or 4 total photosites (16/4)
Blue = 16 quarters or 4 total photosites (16/4)

So that means that Red and Blue are each getting an extra photosite than they would with Bayer, or 33% more information each.

Extrapolating that to the full sensor would mean that we would actually be getting 33% more chrominance than we would with a 12K Bayer sensor

So, 79.6MP / 4 = 19.9MP x 1.333 = 26.5MP of total chrominance resolution.

26.5MP is just about 7K worth of chrominance resolution.

On top of that, this demosaicing we are doing here is rudimentary. The actual math would be looking several photosites away in every direction.

Modern demosaicing gets about 10-15% better resolution than you would otherwise expect, so it's not a big leap to say we could be getting approximately 8K worth of chrominance with this subtractive approach.

I can't say for certain if Blackmagic is using this approach, but if you look at section 99-100 of the patent, they describe how they determine the chrominance of white pixels by using a given kernel (a type of matrix) that includes subtraction of nearby photosites. I need to double check the math to know for sure, but that is where you can find it.
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This is perhaps the biggest point I feel most people are missing with this design. A white photosite isn't just luminance. It captures ALL the colors, so subtracting information based on the nearby colors of the filtered photosites the color values of that white photosite can be accessed for increaded color depth while the straight luminance can also be used to raise the overall dynamic range and base sensitivity. That's pretty clever, and I think the only reason it hasn't been used in the past is that the only way to really make it work is with very high resolution.
 
Indeed: the fact that the sensor is 12k is what allows them to play with the color filter array in new and interesting ways. And the fact that they designed the sensor, the codec, the camera and the edit/color software, taking interactions into account, is what makes it work so well: without BRAW the datarates would be crazy; without Resolve, support for this non-Bayer RAW would be a mess.

I'm really impressed by the long-term planning and big-picture thinking that were involved in the development of this camera.
 
When you think about it - Apple has decided that having full control is preferable over dealing with the outside suppliers. The key lies in being able to execute all parts.

ARRI (co)developed ALEV, its codecs, the cameras and the lens lineup. Most car manufacturers try to control the engine, the body and the suspension on their automobiles. Meaning that, if it can be done, it should be done.
 
Paul F said:
I wonder if there are any competitor patents that were restricting BM development that this will circumvent.
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You know everyone assumed that IP issues was the thinking behind Blackmagic RAW being introduced.

BMD started the development of this codec concurrently with the sensor. They had to be developed together.

Also, notice that RED have switched to DCT based compression ? Komodo has a "different" version of REDCODE. They're right now starting to talk about changing over wholly to DCT based compression (Same as Blackmagic RAW) because high resolution sensors make it very difficult to do high compression and keep the data rates manageable.

I find THAT more interesting because for years REDCODE as been the true strength of RED's cameras. What made RED unique was their use and indeed their IP is based on wavelet based compression.

http://www.reduser.net/forum/showthread.php?182627-Komodo-REDCODE-RAW-Explained

http://www.reduser.net/forum/showthread.php?181858-New-Compression-Ratios

DSMC3 will be DCT.

Now they're moving away from that as well towards what BRAW already is....DCT....


JB
 
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Thought I'd post this here too.
Here are some stills from the Ursa Mini Pro 12K. Shots with people in them coming at a later time.
I'm extremely impressed with the details and colors that you can get from this camera.
I think the team at BMD has achieved something really special.

Both shot with the Sigma 18-35mm.
Check out the links for better quality versions.

Ursa Mini Pro 12K by Note S., on Flickr

Ursa Mini Pro 12K by Note S., on Flickr
 
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swaneon said:
Here are some stills from the Ursa Mini Pro 12K. Shots with people in them coming at a later time.
I'm extremely impressed with the details and colors that this camera can achieve.
I think the team at BMD has achieved something really special.



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That is very pretty
 
swaneon said:
Thanks James!
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One of the bonuses is you also have the option of high res images you can print to go even further and reveal all the texture in that drift wood. (and/or 8K screens... 8K OLED, swoon.)

If anyone is inclined, take a look at the 4K still download from Flickr. Now imagine 12K. Haha. That in itself opens up some interesting possibilities, but it also seems like the tone curve and colour science are very nice, from what we are seeing. Makes the camera all the more appealing.

With that kind of resolution, there are also more possibility for making interesting lock down long takes. So much more detail to explore.
 
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swaneon said:
Here are some stills from the Ursa Mini Pro 12K. Shots with people in them coming at a later time.
I'm extremely impressed with the details and colors that this camera can achieve.
I think the team at BMD has achieved something really special.

Click the photos to get better quality.

Ursa Mini Pro 12K by Note S., on Flickr

Ursa Mini Pro 12K by Note S., on Flickr

If the images are too big, please let me know and I'll resize them.
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Wow those images look great. Nice colors & clarity!
 
ahalpert said:
Possibly. But I wager at the least it would provide enough color info for an HD deliverable.
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ahalpert said:
Dead in acquisition but not dead in deliverable. Plus you get to say it's a "6K" sensor.
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Well, this is basically what the F35 is. A 6K camera which delivers awesome HD. It's part of the reason the image looks so good. Full RGB HD from a 6K sensor. It's also a CCD which adds to the look. But a new camera that shoots great HD will probably not have as much appeal.
 
Sttratos said:
Well, this is basically what the F35 is. A 6K camera which delivers awesome HD. It's part of the reason the image looks so good. Full RGB HD from a 6K sensor. It's also a CCD which adds to the look. But a new camera that shoots great HD will probably not have as much appeal.
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If it can record 6K, it would probably have more appeal because now it's a "6K" camera and not an "HD" camera. Of course, now we're talking about appeal and marketing which can be difficult to predict and might be irrelevant to our own personal choices
 
How will the camera be in low light when shooting HD or 4K? Will it be the same as the Ursa Mini Pro 4.6 G2?
 
boo said:
How will the camera be in low light when shooting HD or 4K? Will it be the same as the Ursa Mini Pro 4.6 G2?
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Similar to a G2 is how I would describe it.

There's some studio / dramatic lighting shots on the BMD website...have you had a look at those ?

JB
 
The BMPCC Pocket 4K is backordered everywhere, is that Covid, high demand, or is there a replacement on the way?
 
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