BMPCC aka BLACKMAGIC POCKET CINEMA CAMERA, a Super 16mm contender -pt2

 

All right, here we go with the geek stuff. One word of caution before you go along and read this.
There is a lot of grief around the web on this camera, but you have to remember this is a Cinema Camera and not in the way Canon is marketing their own… bar the C500, which is the one and only that deserves the title.

Arguably the BMCC Pocket is the cheap miniaturization of an Arri Alexa. Funnily enough, highly regarded cameras like the RED and the Alexa have many of the same practicality problems of the Blackmagic Pocket Cinema. Fact is those do not even begin to cover the word ‘problem’ in typical cinema production scenarios, as it’s the job of the Cinematographer to control shooting conditions to prevent them.

There is no out-of-the-box professional tool out there, there is no magic wands when it comes to shooting video. The statement that pro results do require pro efforts checks, as people always have done when shooting on film.

I guess this is well all this wrath against BM stuff is springing from. Much of the DSLR lovers are amateurish shooting crowd, tending to utter frustration when things don’t shape up quickly. The pros don’t see the big deal. I recall reading this sentence, that I think summed up all of it. It went on something like that ‘amateurs get upset by the pros, thinking that the pros blame their skills while the camera should be blamed’. Well put.

Enough with the introduction, let’s get hands on.

 

Like many other CMOS based cameras, one issue is rolling shutter. Why is this so dreadful? Other than the skew and jello effect, rolling shutter can bring along additional artifacts like smear and exposure changes. The first two are pretty much unavoidable, the last two lesser present in my own experience.
Some people say that it’s not that big deal, as fast pans or whip pans are not every day’s cup of tea. I have to disagree, as when using the GH2 I had micro jitters that would turn the image to be unusable because of the resulting jello+skew combo poison.

Also I find that rolling shutter impacts motion overall. A couple of days ago I was doing a corporate shooting on a C100, locked on a slider, panning very smoothly to the right while moving forward as smoothly. Rolling shutter was there, the corner of the wall skewed when panning, I could not believe my eyes. Miles away from a whip pan, and I had to fix the shot with the Rolling Shutter by The Foundry plugin. For the records, the C100 is not the worst in the list when it comes to Rolling Shutter.

I have not measured RS myself on the BMPCC, but I am here crunching the figures that I found on peer websites. I do not feel the urge of re-doing the tests myself, as these folks are pretty capable of producing reliable result –or at least better than myself, they also seem to have used some hi fi equipment that I don’t happen to own.

I am reporting just some, this is non- exhaustive list

Arri Amira 2ms
Film: 4ms
F65: 14ms
Canon C300: 16ms
BMPCC: 18ms

Cameras with a lot of shooting modes (like the GH4, A7s, RED) shows a multitude of results in terms of RS performance much depending on the shooting mode, so I have just taken the ones that are clean cut.
Broadly speaking 4k has double the RS of a 2k mode, but the RED ONE for instance can keep that around 16ms in 4k.

Next up is dynamic range. This is where much debate goes on, also because the numbers often found in the specs do not make sense in a real shooting environment. The actual USABLE dynamic range is what matters the most, and that’s a fraction of the full dynamic range -normally in the region of 30-40% below the maximum latitude. This has to do with the fact that although the sensor is rated at a certain latitude, the shadows get really noisy and the highlights kind of wonky so that the specs do not make any more sense in a real shooting environment.
The theory then goes much further, because there is a relation between bits and latitude, but it gets pretty technical and beyond the purpose of this article.
Again, I won’t run tests myself but trust results from reliable sources. Samul Hurtado over at www.similaar.com has certainly done his homework, and these are his findings

These facts are pretty clear
A_ the BMPCC is rocking the charts
B_ the BMPCC delivers uniform DR when shooting RAW

The Canon Cinema Camera is absent from the test, but from other resources it does not appear to score much further from the 5dmk3 when shooting in Technicolor mode, which is akin to Canon’s very own LOG mode.

As a side note it seems that the properties of a certain lens can impact the dynamic range, as somehow both the coating used (contrast) and the sharpness (color separation) can impact on the DR, especially when shooting with 8 bit cameras.

To conclude the DR talk with regards to the BMPCC, bear in mind that you want to shoot at 400ASA minimum, but try to nail as many shots as you can at 800ASA if you are in Prores land. If you were shooting RAW, ASA does not matter that much in terms of DR bar the noise level. The cleanest image you get from the camera is at iso 800, thus the BMPCC can be occasionally pushed to iso 1600 without exhibiting too much visible noise.

 

Now it’s the color science turn. As many of you surely know, Blackmagic made it big in the post production industry, via their Resolve software and hardware. The camera market has made them a popular choice among the crowds, other than the pro market.
This is to say that they should know one thing of two regarding color. This has been said many times over, so it’s understood that each camera has to be treated as a different film stock.

The BMPCC (like its siblings) is not ready to shoot out of the box, it needs to go through a hefty grading for its footage to come alive.  This is a sort of ‘buyers beware’ because the low price tag attracts indeed a lot of potential buyers, but don’t expect to run’n’gun with it. This is no DSLR, and the workflow it’s much similar to pro cameras. I won’t describe the RAW workflow in details, such topic would just deserve its own space. However there are plenty of resources over the net, Google is your friend, this is just one of my personal liking

https://www.youtube.com/watch?v=U059jPcjWew

Shooting RAW does not mean that there isn’t any color science behind it. It just means you can tweak the footage a lot and it almost does not fall apart, but there is a king of imprint to it belonging to a certain manufacturer’s will. To my trained eye, this is where the Arri Alexa is the king, to the point that almost any TV series, medium to high budget commercial and Oscar candidate pictures are shot on the Alexa (and potentially, on Amira from now on).
This is how much color is of importance, the war is on resolution, but it’s just pure madness. People see colors more than pixels, and again… you want to fire 6k on a human oval? Resolution matters for CGI, landscapes, aerials, but other than that it’s a marketing gimmick. Sell more pixels, make people upgrade their computers, TVs and all but what makes the heart beat is how color is rendered. Arri had huge expertise from film, and I guess it taught them a great deal on digital, since the D21 at least.

The Blackmagic cameras color science is pretty distinctive, hard to put it into words. However it’s definitely a pleasant one, and found many enthusiasts around the globe. One thing you have to be aware of is how the sensor behaves under tungsten lighting though. This is very challenging for some cameras more than others, for instance the C100 seems to deliver uniformly across the light spectrum. This is a picture that explains the challenges when shooting under tungsten

And here is a valuable free resource to get started with your grading on BMPCC-powered footage

http://www.captainhook.co.nz/blackmagic-cinema-camera-lut/

 

The last point is regarding sharpness. Again I will reference finding that are available on the web, on particular from a cinematographer I have been following, Corey Robson www.coreyrobson.com alongside the test from Samuel Hurtado.
The test conducted by Similaar shows that there is little if not any sharpness difference between the BMPCC in Prores or in RAW mode. You still want to go RAW because that’s where the DR is.

These are the charts for your own consultations, with embedded moire from the BMPCC :)

It is pretty astonishing to notice how similar the sharpness test are. I would happily conclude that although the BMPCC might not be as sharp as the C100 (or the C300 for the matter) as these machines downscale internally from a 4k sensor, certainly it is no slouch compared to the Arri Alexa !

 

 

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