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Attila Bakos

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Everything posted by Attila Bakos

  1. Can you send me a still that shows this pixel? I wonder if the location is the same...
  2. Interesting you say that because I have a single pixel in the center of the screen as well, only in 6.2K ProRes RAW, it's not visible in 4.8K. If it's a bad pixel I'm not sure how Atomos could fix that, and why it's there in 6.2K and not in 4.8K. Even 4.8K60 is fine. Anyway, this is what I'm getting: https://drive.google.com/file/d/1m1w9o4LmO85ER9AWg3OFgQnJK1Q9cmMR/view?usp=share_link In the first half I pressed record on the Fuji, and I got like 12fps. Then I turned recording off and back on, and it was fine after that, as you can see in the second half. And this is one way to trigger it (download before watching): https://drive.google.com/file/d/1G0J2dvH2IS0mZIWlee0DZ5Rf4xvz97IK/view?usp=share_link But basically any change can trigger it, like tapping on the screen to refocus, it's totally random.
  3. Does anyone use the X-H2s with a Ninja V Plus? Some of my 6.2K 24fps clips are stuttering badly, only every second frame is different, so it's basically 12fps. It happens and goes away by random camera actions. So if it's good and you don't touch the body it stays good. But even refocusing can make it bad. The camera is in boost mode, I hit recording on the body as well, newest firmware everywhere. The cable I'm using is HDMI2.1 8K60 certified, should be more than enough. I'm out of ideas really, I hope it's a user error but I fear that it's not.
  4. To anyone who is interested in recording ProRes RAW with the X-H2s, I just got confirmation from Fuji that they convert X-Trans to Bayer in the camera, as I suspected. Because the two patterns are different, you have to calculate what's not there. So let's say at a given pixel X-Trans stores red but for Bayer we need blue. I asked Fuji if they interpolate this blue using the surrounding blue values in the X-Trans pattern or they just copy the value of a blue neighboring pixel. The latter is faster but more prone to artifacts. Unfortunately I received an one-liner that this is proprietary info. I'll know more when I test this out myself, I'll receive a Ninja V+ in the following days.
  5. I don't have the GH6 unfortunately, but I checked a ProRes HQ V-Log L sample and the chroma channels are very good. The Fuji chroma smoothing is there in all internal and external recordings, the only exception is ProRes RAW. As I mentioned earlier it's weird though. ProRes RAW can not hold X-Trans data, it's designed for Bayer. Atomos already confirmed to me that they don't modify the raw feed. I'm still waiting for Fuji's answer, but the only thing I can imagine is they demosaic X-Trans in the body, then remosaic it into Bayer and send that to the recorder. While it works it is kind of a trick, and when we compare ProRes RAW features to BRAW, one of the main things that sets them apart is that ProRes RAW is not debayered and thus more raw-like, while BRAW is partially debayered. So I'm not sure if we can talk about being not debayered as an advantage here, as the raw feed that the Ninja V records is actually already processed by the camera. And if you go into details, demosaicing is basically filling the "holes" in the R,G,B planes by interpolation methods, using the pixels that are known. See the "holes" here (it's for Bayer, but you'll get the point): Now if you remosaic the R,G,B planes to Bayer, you have to throw away about half the originally known values, as the pattern is different. You exchange them to interpolated values and send them to the Ninja as if they were the known values from the sensor. I have my doubts about the quality of this method, but I will test it when my Ninja V Plus arrives.
  6. Revised my findings, the previous comment can be deleted. (Both bodies are equally bad in 1080p.)
  7. I read some comments about the 1080p quality being worse on the X-H2s than on the X-T3/4, and I thought it's nonsense, but after a few quick tests it is worse indeed, for some reason the moiré/aliasing artifacts are more pronounced. Not sure about the reason yet, maybe the readout is different.
  8. Recently purchased the X-H2s, and you know me, the first thing I look at is chroma resolution. Just dropping this in, on the left side you see the Cr channel of an EOS R 4K C-Log 8bit 4:2:0 recording (about 420 Mbps), on the right side it's X-H2s 4K F-Log 10bit 4:2:2 (about 615Mbps): Don't get me wrong it's better than the X-T3, but this smoothing can still lead to loss of color. I really wish we could turn it off and deal with color noise in post. ProRes RAW helps but it's a mystery to me. RAW on the X-H2s has the X-Trans pattern, obviously. However, it gets magically converted into Bayer in the ProRes RAW file. I had discussions with people who are involved in ProRes RAW->DNG conversion, also did my own test with Raw convertor (resulting DNG has Bayer pattern) and it seems that the data that arrives to a Ninja V recorder is already Bayer, even though the sensor is X-Trans. I'm still trying to confirm all this but if the body demosaics the X-Trans pattern and remosaics it into Bayer, then it's kind of a hack which in some cases can lead to artifacts.
  9. Ah yes you are probably right 🙂
  10. Yes the log profiles are worse. Btw when you're testing chroma components in Fuji files, make sure to skip the first few frames, those are worse than the rest.
  11. Attila Bakos

    Panasonic GH6

    It's not the red channel that's blurred but the chroma components in the YCbCr format, that is Cb, and Cr. Both Cb and Cr are blurred the same way, but I used Cr for demonstration as it shows the issue a bit better. Btw Cr is red minus luma, so you are not that far from the truth 🙂
  12. Forgot to mention that in this test in hybrid mode the decoding was done by the iGPU and the encoding was done by the dedicated GPU (as I encoded to 4:2:0), so they can really work together.
  13. No, I'm referring to NVIDIA/AMD. I just did a test for you. I have a Lenovo Legion 5i Pro laptop with an i7-12700h CPU and a 3070Ti GPU. I loaded a 2160p 4:2:2 HEVC F-Log clip to Resolve, added a LUT and some tweaking. With hybrid mode enabled (that is Resolve can use both internal GPU and the dedicated one), I get smooth 25fps playback with low CPU usage and rendered out the clip with the H.265 Master preset in 18 seconds. Now if I switch to dedicated GPU only mode, I get 21-23 fps playback and high CPU usage and the clip rendered out in 41 seconds. So basically with 10th or higher gen Intel CPU I get 4:2:2 support in addition to what the GPU already offers, no need for a Mac (for this).
  14. But what if you have an Intel processor with 4:2:2 decoding support and a dedicated GPU? I was under the impression that they can work together.
  15. That's true, however Intel QuickSync supports hw encoding/decoding of 4:2:2 HEVC since Gen10. Better than nothing 🙂
  16. How do you import the video into GIMP? We can move to private message.
  17. No I'm not selling it yet, but I validated my results with ffmpeg as it can extract the chroma channels as grayscale and I can safely say that my results are correct. How do you extract the channels in gimp?
  18. Here is a short demonstration of the Cr channels: https://drive.google.com/file/d/1veiqGodXKxerdNF_ksqLlAnFWbGQUtEe/view?usp=sharing 8bit is rubbish, never ever use it. 10bit is somewhat better than on the X-T3/4, but the chroma smoothing is still there, ProRes doesn't seem to help either. Interestingly the X-H2s seems to have more smoothing than the X-H2. As much as I love Fuji for stills, I think I'll stick to other brands for video as I'm very sensitive for this kind of stuff, but for 99.9% of Fuji video shooters this is still a non-issue I guess.
  19. Thank you for all the clips, I hope I can take a look at them this evening.
  20. It's not important to shoot at the same time for this test, if the light is more or less the same then it's fine. When you shoot with other cameras, please use a format that's encoded in YCbCr (h.264, h.265, ProRes for example), as raw won't have this problem.
  21. Please shoot something with lots of fine detail and varying colors at infinity focus (trees with autumn colors are the best, check my youtube video I posted in this topic), both h.265 and ProRes. When it comes to h.265, the higher bitrate the better, and ProRes should be 422. UHD or higher resolution is fine. When comparing both cameras, please use the same scene with the same settings. F-Log and/or F-Log2 please. I know I ask a lot, but if you have other cameras as well, Canon/Sony/Panasonic, it would be nice to see them as well. The issue might not be obvious until you start to compare it with other cameras.
  22. Finally some noise in the Cr: https://www.dropbox.com/s/mesy1evzib28hb2/DSCF0234_Cr.mov?dl=1 Noise is good in this case. When you have a chance to do more, please use 422 instead of LT, I was told that the difference in quality was noticeable in the X-H2(s), and minimal between 422 and HQ.
  23. I downloaded the 8K video sample from the bottom of this article: https://www.photographyblog.com/previews/fujifilm_x_h2_photos It's 7680x4320 10bit 4:2:0 H.265 29.97fps, but only 100Mbps. 4:2:0 means that the chroma resolution should be 3840x2160. So I put the clip on a 3840x2160 timeline, and on the right side you see the Cr channel with added contrast for better visibility: https://www.dropbox.com/s/e04fm6oc5ac9qbz/X-H2_chroma.mov?dl=1 I'll let you judge this, but I don't like what I see. Higher bitrate might help, or ProRes as well, but the chroma processing is still here with us 🙂 And this is not even F-Log where the issue was more prominent in the past.
  24. Thanks, but it is hard to judge based on this shot. I need something far away at infinity focus, something like I posted earlier, if that's possible. And please shoot it in F-Log, or F-Log2.
  25. Haha, I started reading this topic today and in the middle if it I wanted to ask you guys for some footage. Now I don't even have to, that's awesome 😄 Some distant forests would be nice, like in this example: https://youtu.be/7-RHHAUuI6s?t=466 Autumn is great for testing this kind of stuff. And yes, h.265 and ProRes please.
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