New, faster Metabones Speedboosters for BMCC & BMPCC

Pocket + pocket_speedbooster + sigma 18-35 f/1.8 --> 30-60mm f/3.0 full-frame-equivalent shooting 2K RAW with 13 stops of DR for a bit more than $2K --> I love living in the future
 
"The Nikon 50mm F1.2 is transformed into a 29mm F0.74 on the Blackmagic Pocket Cinema Camera."

"It’s with the new Sigma 18-35mm F1.8 that I feel this adapter is a massive breakthrough. The two perform superbly together.
On the Blackmagic Cinema Camera the Sigma actually breaks a record – the world’s fastest Super 35mm zoom.
A stunning 11.5-22.5mm F1.1 with the new BMCC Speed Booster.
It goes to F1.05 on the Pocket Cinema Camera and the wide end benefits from actually being wide!
Nearly 28mm in full frame terms."

Andrew Reid
 
Yeah the math is hard to get your head around with this one. What that tells me is: finally you can get wide on the BMPCC, making lenses choice a lot less complicated!
 
The math for the speedboosters is very simple: multiply the original crop factor (2.9x) for the speedbooster factor (0.54x) and you get the new crop factor (1.6x) --> Regarding FoV and DoF, the pocket becomes APS-C, as simple as that. The only complication is that ISO gets multiplied by 3.5 (divided by 0.54^2) (so, ISO 100 is now ISO 350).
 
Samuel H said:
The math for the speedboosters is very simple: multiply the original crop factor (2.9x) for the speedbooster factor (0.54x) and you get the new crop factor (1.6x) --> Regarding FoV and DoF, the pocket becomes APS-C, as simple as that. The only complication is that ISO gets multiplied by 3.5 (divided by 0.54^2) (so, ISO 100 is now ISO 350).
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From nofilmschool (http://nofilmschool.com/2013/12/bla...amera-super-35mm-new-metabones-speed-booster/) quotes they put it in this way:

The new 0.58x Speed Booster reduces the crop factor of the BMPCC from 2.88x to 1.75x, and produces the largest aperture optics currently available, with a maximum output aperture of f/0.74. For example, a 50mm f/1.2 now becomes a 29mm f/0.74, and the Sigma 18-35mm f/1.8 becomes the world’s fastest zoom lens at 10.5-20.3mm f/1.0 with stunningly sharp performance.

Is the actual light recieved increased? How does a 50mm 1.4 lens on full frame compare with the same lens on BMPCC with this speedbooster given they both have ISO 1600? I mean theoretically.
 
stokstad said:
From nofilmschool (http://nofilmschool.com/2013/12/bla...amera-super-35mm-new-metabones-speed-booster/) quotes they put it in this way:

The new 0.58x Speed Booster reduces the crop factor of the BMPCC from 2.88x to 1.75x, and produces the largest aperture optics currently available, with a maximum output aperture of f/0.74. For example, a 50mm f/1.2 now becomes a 29mm f/0.74, and the Sigma 18-35mm f/1.8 becomes the world’s fastest zoom lens at 10.5-20.3mm f/1.0 with stunningly sharp performance.

Is the actual light recieved increased? How does a 50mm 1.4 lens on full frame compare with the same lens on BMPCC with this speedbooster given they both have ISO 1600? I mean theoretically.
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A correct explanation is it gives you what f/0.74 performance would be on such a small sensor, but not on a normal sensor. Crop factor reduces light input, and reduces perceived DOF vs field of view.

WHat a shockingly small number of people understand is that the longer the lens (in mm) the larger the hole is that represents a particular f-stop. The hole inside an 85 mm 1.2 is much larger than the hole in a 50mm 1.2 This makes sense, because the wider the lens, the more light it gathers to project on your sensor (it's simply seeing wider, so seeing more light emitting or reflecting points in the scene), so if the hole were the same size rather than adjusted for focal length you could not calculate exposure easily.

So for example on a half-inch sensor EX1/handycam camera, the built in zoom lens might be f 1.8. But to give you a 50mm field of view, you need something like a 10mm ultra-wide angle lens (in 35mm terms). f1'8 on a 10mm lens is actually a very small hole in the lens tube. In terms of thinness of depth of field and light gathering, for the same field of view, you can see it this EX1 lens like full-frame a 50mm f22 (my math may be off, but you get the idea) as at f22 the hole in a 50mm full frame lens would be the same size as f1.8 on a 10 mm lens.

So the 50mm 1.2 does not become or behave like a 29mm f/0.74 would on a larger sensor. It behaves a bit more like a 50 f 1.2 would on a stills definition of "full frame" - but still with a 1.75 crop factor. Really all they've down is reduce the crop factor, period.

This is also why doublers reduce your F-stop. They are going in the opposite direction. f2.8 100mm doubled through glass attachment to 200mm loses a stop and becomes f4.
 
Um....here's what matters: The image's FOV is wider than what the native camera can do AND it's brighter with no apparent loss in detail or sharpness (sometimes even looking sharper). Everything else is gravy. All that other technical detail is nice but.... :)

Your already good camera is now...a great one.
 
just found out from phillip bloom's review that this adaptor "does" work with "G" type lenses so aperture can be changed via the pocket camera.

very nice!

david
 
stokstad said:
Is the actual light recieved increased? How does a 50mm 1.4 lens on full frame compare with the same lens on BMPCC with this speedbooster given they both have ISO 1600? I mean theoretically.
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It is easier if you compare it with an APS-C camera, with a 1.6x crop factor. Put a 50mm f/1.4 lens on both and they will have the same FoV and DoF, but the image will be 1.75 stops brighter in the pocket.


It does increase the amount of light that hits the sensor, per surface area (it is basically a loupe that concentrates the photons).
 
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Ian-T said:
Um....here's what matters: The image's FOV is wider than what the native camera can do AND it's brighter with no apparent loss in detail or sharpness (sometimes even looking sharper). Everything else is gravy. All that other technical detail is nice but.... :)

Your already good camera is now...a great one.
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Your seeming lack of desire to deeply understand technical details and learn new things is why you are not a top DP. Talk to David Mullen, or Deakins, or any of the top guys, they know all this stuff, like the backs of their hands.
 
Samuel H said:
It is easier if you compare it with an APS-C camera, with a 1.6x crop factor. Put a 50mm f/1.4 lens on both and they will have the same FoV and DoF, but the image will be 1.75 stops brighter in the pocket.


It does increase the amount of light that hits the sensor, per surface area (it is basically a loupe that concentrates the photons).
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Yes but signal to noise is the same, as signal to noise is determined by total light received as information for creating an image (assuming the small and large sensors were the same except for size).

The smaller sensor is receiving more light per square inch, but on the larger sensor you are zoomed out from any noise, so you get back that stop in the noise floor.
 
You are doing some double accounting there. Noise depends on the sensor, and it hasn't changed; signal is doubled with a 0.71x speedbooster. I will give you that full well is a sensor thing and it is unchanged, so DR is not altered.



I will add a small bit to my previous statement (and also correct it slightly, it is 0.58x, not 0.54x):

The math for the speedboosters is very simple: multiply the original crop factor (2.9x) for the speedbooster factor (0.58x) and you get the new crop factor (1.7x) --> Regarding FoV and DoF, the pocket becomes APS-C, as simple as that. The only complication is that ISO gets multiplied by 3 (divided by 0.58^2) (so, ISO 100 is now ISO 300, but with the same noise as you previously had at ISO 100).



I own a regular speedbooster which I use on my NEX, and this definitely the easiest way to think about it: the camera is now FF, ISO is twice as what the camera thinks (so it is 400 if the camera says 200), and ISO 3200 (1600 if you ask the camera) is now useful
 
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I am still unsure how DOF is changed. You are essentially just putting wider albeit faster, lenses on a super 16 camera. I can't see how that will be the same as an equivalent focal length and speed on super 35mm.
 
Adam J McKay said:
I am still unsure how DOF is changed. You are essentially just putting wider albeit faster, lenses on a super 16 camera. I can't see how that will be the same as an equivalent focal length and speed on super 35mm.
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Wouldn't effectively widening the aperture reduce the DOF? The Speed Booster widens the aperture by about the same amount as it reduces the effective focal length, so the DOF of the original lens is effectively preserved. Or is that what you were saying?
 
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