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BlackMagic Pocket Cinema Camera 4K
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  • The previous BMPCC wasn’t known for its low noise. It produced a fantastic picture, but it wasn’t exactly a low light performer. Fast forward to the BMPCC4K and things have changed, a lot. The new camera has dual native ISOs of 400 and 3200. However the camera will switch automatically to the upper gain circuit at ISO1250. Using ISO settings above or below those two native settings will have an effect on dynamic range, but only minimal.

    https://www.redsharknews.com/production/item/5766-we-ve-tried-the-blackmagic-pocket-cinema-camera-4k-here-s-all-you-need-to-know

  • @bannedindv specs provided by the shooter of the Bubblegum video:

    • RAW 3:1 4K DCI
    • 24fps Project / 60fps Off-Speed
    • ISO 400, 1250, 3200, 5000
    • Samsung T5 SSD through USB-C

    DJI Ronin-S

    • Metabones EF to MFT T Speedbooster XL 0.64x
    • Shot with Contax Zeiss MM primes: 35/f2.8, 50/f1.4, 85/f1.4, 135/f2.8 + Hoya Pro NDs
    • 95% Ronin-S / 5% handheld.
  • I find the lee filter swatches very useful. There is a great app for android and iphone.

    http://www.leefilters.com/lighting/colour-details.html#798

    The x and y are the coordinates in the CIE 1931 colorspace, which is the theoretical reference of every color we see and are able to reproduce, and then some presumably.

    @Lohmatij I agree with the absolute subjective dimension of colour, there is no way to determine if we two perceive a given wavelength in the same way. Any comparison is done through language. Wittgenstein's Remarks on color is a fascinating though pretty demanding read.

    Hope I am not hijacking this thread.

  • @eatstoomuchjam

    I wasn’t correct when I mentioned purple “spectrum”, the proper way would be to say “a group of purple colors.” I was talking about XYZ color model which can’t describe those colors accurately, and because RGB color model and all existing RGB color spaces are based on it, we can say that they will have trouble with rendering of those colors too.

    Keep in mind that while some colors, like violet, can be described as a a single wavelength , some colors has to be described as a combination of different wavelengths. Purple doesn’t have any corresponding wavelength, it’s a combination of pure blue and pure red, 2 colors on the opposite side of spectrum. The other simple example is color “white”, which consists of equal combination of all visible wavelengths.

  • The last shot in the Bubblegum video is of the operator holding what looks like a Ronin S, FWIW.

  • @Lohmatij "for example there is a big chunk of purple spectrum which just can’t be described in math."

    This statement seems ridiculous. What we perceive as colors are portions of the visible spectrum of wavelengths. Purples are the wavelengths at the short end of the visible spectrum (wavelength 450–400 nm, frequency 670–750 THz) and consequently can be easily "described in math."

    If you want to say that no existing color space can accurately render every possible shade of purple, on the other hand, that may very well be true. I'm not familiar enough with color spaces to say.

  • somewhat unrelated question. I've been studying camera movement lately. We all the slow motion shots mostly handheld? thanks.

  • Oh my god. What a babe.

    And the footage looks damn good too. But maybe I’m blinded by the model’s beauty.

    She’s thrown off my gamut response.

  • @libertas

    Color is very subjective, there is no way to tell how different people perceive color, you can only make tests of how different people distinguish different colors. Studies did show that around 8% of men can’t perceive some colors, so they have a color blindness of some kind.

    The only thing you can measure is how color on screen corresponds to color in real life. The problem here that there is no technology (real or futuristic or imaginable), which can fully simulate all light characteristics of a real subject, so you always have to make a simplified model for the sake of comparison. Even XYZ color space (the base of all color models we use in our days) can’t describe all colors accurately: for example there is a big chunk of purple spectrum which just can’t be described in math.

    There is also no proper way to compare eye “parameters” to monitors and cameras. Everything you do is subjective: something can look good enough now and really bad after few decades. Eye is a really unique instrument, I don’t think there will be a day anytime soon, when we will be able to completely “simulate” it. Just a simple example: in Soviet Union there were experiments which tried to find out what is the minimum amount of light the eye an register. It was found out that after a proper adaptation (staying in a dark room for long time) a person could register a single photon (!!!) of light.

  • @Vitaliy_Kiselev This is incorrect. Color science actually started from such experiments and advanced extremely.

    Do you mean psychological experiments that try to determine the nature of perception or experiments that measure physical characteristics of light? I would like to know more, if there is some soviet type experimentation that is not well known.

    As per gamut and DR I think these diagrams can clear things up a bit. Note that the DR of what our eyes can see is adaptive, meaning that night vision and seeing in strong sunlight are two different functions.

    image

    image

  • @markr041

    I’d recommend you to download DaVinci Resolve Manual and read it throughoutly. You’ll get answers and better understanding for most of your questions.

    For proper gamut transform I’d recommend using ACES or “DaVinci Color science”, it’s not gonna clip your DR or color gamut (LUT’s will). You can use it for BMPCC as well.

  • Blackmagic Film Log has its own gamut, it's not Rec709. (You can easily test this with the Color Space Transformation tool in Resolve.)

    The difference between Raw and ProRes on all their cameras btw. is that Raw is 12bit and ProRes is 10bit.

  • @Lohmatij Oy! Here we go again (talk about damn).

    I am talking about REC709 color gamut. Not DR range. I do not understand how anyone can read my above posts and still confuse DR with color gamut. I get that one code word for both DR and color gamut (REC709) is confusing, but still...And yes, gamut and gamma sound and look similar too, so I could see why there is confusion, but let's get back to the issue:

    Sony offers Sgamut, Panasonic offers V-gamut, Canon has C-gamut. These are all color gamuts that contain colors beyond the REC709 color gamut (get it, color gamut, not DR). So, what is the equivalent extended color gamut for Blackmagic cameras? Is there one? what is it? where's the spec? Every original BM 4K camera .mov clip I have downloaded is REC709 color except the one RAW clip.

    Is the extended gamut called "BMD Film"?

    Btw, some guy is posting "HDR" videos made from the original downloaded BM clips. The original clips are all REC709 color, so these are bogus HDR videos in terms of color.

  • @markr041

    Every damn single camera on the market already records beyond Rec709. Rec709 is just 5 stops of latitude, I can’t even imagine someone will shoot anything with such a shiity DR in our days.

  • @bannedindv I downloaded an original video clip from the camera. The metadata said it was REC709 color. I do not know whether it was shot in "film" mode, but it sure was flat and lacked color (which is good).

    If we had an original "film" mode video clip we can see right away what the color gamut is from the metadata. I have not seen anywhere Blackmagic indicating it has a special wide color gamut, but I could have missed it. Nor do I see a camera menu item for color gamut type (but I could have missed it). There has been no mention of HDR in any of the PR about the camera (and I do not mean HLG).

    I am just asking the question about whether there is wide gamut color or not from the camera. If so, I am sure DaVinci Resolve Studio will have the right transform to REC2020 color (the correct math). If not, then it is not possible to create HDR video taking advantage of its wider true color gamut spec using this new camera. Right now, Resolve Studio has the transforms for Sony SGamut to REC2020 and Panasonic V-gamut to REC2020, so I know with Sony and Panasonic cameras you can produce HDR videos with more true colors than REC709 (whether or not it provides the full REC2020 gamut and ignoring bit depth).

    Of course you can take advantage of the extended dynamic range shooting RAW or shooting in film mode - let us not confuse the extra dynamic range and different luminance mapping of HDR with the issue of number of colors (or number of color gradations - bits). Without colors beyond the REC709 gamut recognized by the camera sensor or recorded, one is missing the other advantage of HDR. And thus it is NOT HDR.

  • From my experience with Blackmagic cameras “Film” gamma doesn’t clip anything compared to RAW footage. The only difference few years ago was that Prores footage defaulted to 422 color space, while RAW was 444, but I could never see any practical advantage in it (I’m not that much into SFX).

    In fact when you develop RAW in DaVinci Resolve you have same 2 settings (Film and Video) so after extensive testing I started to shoot with Prores “Film” gamma.

    As for HDR and Rec2020: it’s just a way to map very bright values on your final image. It doesn’t have anything to do with a recording format, in fact you can make HDR cartoon or HDR game and not use any camera at all. Of course the wider the DR and gamut of your camera the more logical it is to use Rec2020 for final output, so BMPCC makes perfect sense to use it. In the end it what’s your client asks for, and if you are gonna output in HD it’s 99% gonna be Rec709.

  • @markr041

    "Loading a REC202 LUT does not magically increase the REC709 color space."

    Yeah, no kidding... in Film Mode aka LOG I don't believe it's clamping your available color Gamut to REC709 outputs...

    Probably the standard video output setting is clamped to REC709 Gamut...

    If there is information anywhere about the Film Gamma/Gamut being clamped to REC709, let us know - otherwise I think it defaults to WideGamut without clamping... but I could be wrong.

    I totally know about Color Gamuts and Gamma being two different things... so, don't worry about me, I'm not your average LUTard . Just saying if you wanted to clamp your unmitigated signal into a BT2020 Clamped Gamut you could probably do that easily enough.

    RAW sensor data should definitely not be clamped unless you clamp it or set your project gamut in resolve

  • 4k downsampled to 1080p seems "muddy" to you? Maybe you're using the wrong software to downscale - with a good lens and decent bitrate, downscaled 4k tends to be razor sharp for me. "Punchy" is subjective, but by adjusting curves/contrast/saturation, you should be able to make just about any image at any resolution "punchy" enough to suit your tastes (possibly with the trade-off of banding and/or blown highlights/crushed shadows).

  • @libertas

    Also there is no objective way to determine the colors that are actually perceived by each one of us.

    This is incorrect. Color science actually started from such experiments and advanced extremely.

  • Also there is no objective way to determine the colors that are actually perceived by each one of us. Information in the file corresponds to light emitted by the display. At any point in the process from lens to our eyes via all the technology involved, information and subsequently perceived color may be altered with a multitude of means. But generally if you don't get the shot, it costs time, money or both to recreate what is missing. I am really fed up with 8 bit 420, it seems broken, 4k of course becomes 422 at hd. But it seems muddy, maybe some kind of similar processing is going on with the Bmpcc, prorez hq doesn't seem as sharp and punchy as it can be.

  • I'm sure there are cases where perfect re-creation of the colors that were perceived at the time a thing was shot are useful, but short of walking around with a densitometer and sampling everything, that is pretty unrealistic. Plus colors in the real world are made up of more than 256 levels of red, green, and blue and yet a lot of us manage to get by with 8-bit codecs.

    I'm not really sure what the problem is if (in grading), midtones are introduced/restored that weren't present in the original lossy image.

  • Your first statement is a claim that the cameras I mentioned do not actually "see" the full REC2020 color space. I am sure that is partly true, but they sure see more than the REC709 color space than is recorded by the camera that is the subject of this thread.

    No cameras had been mentioned (except it is in BM topic). To make your statement you need to know spectral sensitivity curves, that you don't.

    There are colors in the REC2020 space that are simply not included in REC709, right? So the REC709 clips are missing colors in the REC2020 gamut. So the math transform makes up colors that are not included? And you think that is perfectly fine?

    Yes, it is all fine. Math transform moves point in 3D space.

    You'll be surprised that almost all cameras actually "make up" colors in their JPEG engine to make picture look better, and this includes playing with saturation.

    We are talking about recreating accurately the colors that exist in the world. Making up colors that are not recorded using math or using black magic (hah!) does not achieve that end.

    Actually it does. If camera is unable (due to sensitivity curves) to instantly accurately get the color, but is able to do same or even more saturated colors via complex algorithm (even using scene or object recognition) - it makes no difference for viewer. And most cameras work such way now.

    The increase in the color gamut from the math transform is fake color. I assumed in my statements it is understood we want actual color not fake color. So, as I said, the math does not "magically" turn REC709 color to (true) REC202 color - it does not widen the gamut other than by creating false colors.

    No such thing as "fake color" exist.

    To repeat again - you can perfectly get Rec 709 clip and grade it in Rec 2020 space in any good modern editor, most of the time it will be very little difference with Rec 2020 output by same camera. As in reality for most cameras you need to give up in sensitivity and hence - get big sales hit, to be able to go much wider than Rec 709.

  • I think you are adding to confusion. Nothing I said was "strange" or misleading or false.

    Your first statement is a claim that the cameras I mentioned do not actually "see" the full REC2020 color space. I am sure that is partly true, but they sure see more than the REC709 color space than is recorded by the camera that is the subject of this thread. Which is the point.

    Your second statement adds to confusion. Let's try to be clear: There are colors in the REC2020 space that are simply not included in REC709, right? So the REC709 clips are missing colors in the REC2020 gamut. So the math transform makes up colors that are not included? And you think that is perfectly fine?

    "It is just math" is irrelevant. We are talking about recreating accurately the colors that exist in the world. Making up colors that are not recorded using math or using black magic (hah!) does not achieve that end.

    We observe in the real world more colors than the REC709 color space. REC2020 allows us to reproduce more of the colors we see than REC709. We do not see math transforms of REC709 color, anywhere in the real world.

    The increase in the color gamut from the math transform is fake color. I assumed in my statements it is understood we want actual color not fake color. So, as I said, the math does not "magically" turn REC709 color to (true) REC202 color - it does not widen the gamut other than by creating false colors.

  • @markr041

    I think you told lot of strange things, Let's clear them out.

    Actual Rec 2020 make sense only if sensor sensitivity curves allow going our of Rec 709 primaries. For most cameras put good sensitivity in priority so they ever barely touch Rec 709 or go slightly more.

    Good editor if you import Rec 709 clip in the Rec 2020 project will do all for you. And yes, grading Rec 709 in Rec 2020 project does increase color gamut (of course it won't be true colors camera saw), it is just math.