Blackmagic Production Camera 4K... sensor smaller than true Super35 ?

[Marcello Mazzilli]

I have ordered (3 month ago or so) a BMPC 4K .. still waiting.
Now I've heard rumours that the sensor is not really Super35mm size but slightly smaller.. This means that lenses ratio will be different (probably just by 1-2 mm factor) than what you should expect from a standard Super35mm sensor. Can somebody confirm or deny this?

If this is true.. this is a second omission from Blackmagic .. together with the un-availability of DNG format at the moment.. not very nice to know.

Thanks, MM

[Stephen Brenner]

The tech specs for the sensor are right there on their web page.
It's not like they are hiding this info.

[Marcello Mazzilli]

Blackmagic says ... Effective Sensor Size is 21.12mm x 11.88mm (Super 35).
According to Wikipedia (Super 35 - Wikipedia, the free encyclopedia) there are many Super 35mm formats but it seems that BM’s “Super 35mm” is smaller than the smallest of these.
Can somebody help? Is there a STANDARD Suoer35mm format?

[Bruce Watson]

Originally Posted by Marcello Mazzilli

Is there a STANDARD Super35mm format?

There is not a single standard, no. There are a number of standards under the umbrella name of S35. The Wikipedia page you quote is correct AFAIK.

The largest frame size was used during the silent era -- basically 24.9 x 18.7 mm, giving an aspect ratio of 1:1.33, or 3:4, which became the common aspect ratio for television. In the silent era, again AFAIK, the capture format and the distribution format were the same. When sound was added, this changed, and it changed over and over and over as the technology for sound evolved. Which is why there are so many S35 standards.

[Marcello Mazzilli]

So can we say that Blackmagic format is ok? Will a DOP use to work with 35mm find anything strange?
M

[Marcello Mazzilli]

But many sites give Super35mm size as 24,9 x 14,0 mm.. that is a 16/9 resolution (as needed for a Digital UHD camera for example) and is quite bigger than BMPC4K size isn't it? The same lenses on this two different sensors/films will produce quite a different result!

[Bruce Watson]

Originally Posted by Marcello Mazzilli

But many sites give Super35mm size as 24,9 x 14,0 mm.. that is a 16/9 resolution (as needed for a Digital UHD camera for example) and is quite bigger than BMPC4K size isn't it? The same lenses on this two different sensors/films will produce quite a different result!

24.9mm is the largest width available between the sprocket holes of 35mm filmstock. That's the maximum, if you try to go bigger, your image starts to show the sprocket holes. In cinema work, this is the maximum width of the image. The image width can be smaller on 35mm film, but no wider.

The height of the image, when using 35mm film, was determined by the spacing between the sprocket holes (perforations, or "perfs"), and had to be in whole numbers of sprocket holes used to pull the film down through the camera (or through the projector, same principle). So, the original frame size was called 4-perf (or 4-perf pull down). This resulted in a frame size of 24.9 x 18.7mm as I stated previously.

You want a full explanation of pull down, and how it effects frame size, Wikipedia is your friend.

That said, 24.9 x 18.7mm isn't Super35, or S35. Turns out, S35 is smaller.