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Attila Bakos

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Everything posted by Attila Bakos

  1. Quite the opposite, this is what my video is about. There is no RGB in the original file, only YCbCr. RGB is constructed from YCbCr. The Red channel you see in Resolve/Premiere/etc is detailed because it is constructed from Y and Cr. Since Y is full resolution and very detailed, the resulting Red channel will be detailed as well, even though Cr is heavily processed and has less resolution. So if you want to know why your image lost colors in detailed, colorful areas -even though you see a detailed red channel- then you have to go back to the original channels and examine them. And that is Y, Cb, and Cr.
  2. The X-H2s is better, less blocky, but I was expecting a bit more as well. Maybe ProRes internal is better, but the guy who provided the clips doesn't have a CF express card so we couldn't test that. When he gets one he'll send me another comparisons. What I could test is ProRes RAW HQ external, and it's really good, but it's 15GB for one minute.
  3. Okay, for those who find this kind of stuff interesting, here is a comparison of Cr channels (with added contrast for easy visualisation) from the C70, X-T3, and X-H2s: https://www.dropbox.com/s/pbfjdx4c2zxhhzq/chroma_compare.mp4?dl=1 C70 is C-Log3, 100Mbps X-T3 is F-Log, 400Mbps X-H2s is F-Log, 360Mbps There is definitely an improvement over the X-T3. (I only received this files from someone, so I can't do other comparisons.)
  4. Ignore my comment about the X-H2s having better chroma channels. Just received the same clip shot on an X-T3 from the guy who provided the X-H2s clips, and the chroma channels are good on the X-T3 too, at least in this shot. More extensive testing is needed. And I might just as well upgrade my X-T3 to the latest firmware and re-test it, who knows... 🙂
  5. I just had a chance to take a look at some X-H2s originals shot in F-Log and F-Log2 in H.265, and it seems to me that the chroma smoothing is way less aggressive in this camera. It's still there, but it won't cause problems I think. This is just my first impression, not a deep analysis. And now you can completely get rid of the smoothing by shooting raw to an external recorder, I tested this with a ProRes RAW HQ clip. What I couldn't test is ProRes internal. I also noticed that the H.265 files are now tagged with the BT.709 matrix coefficients instead of the BT.601. This will definitely solve some interpretation issues. One small downside is that the files are no longer full range (at least the F-Log and F-Log2 originals I received), they only use the limited range, so we lost some precision here.
  6. I want to see badly how the chroma channel of F-Log looks like on this new body, but noone seems to have shared any originals. Let me know if you find any.
  7. Well, then my LUTs work for the X-H2s as well, thank you Fuji 😄
  8. Just noticed that the official F-Log LUTs for the X-H2s are exactly the same as for the X-T3/4. Even the Eterna LUT, which is a well defined look. If that's the same, then the F-Log source that it's applied on has to be the same as well. Makes me think... did Fujifilm tweak color data coming from this new sensor to match X-Trans IV sensors, or the sensor is not that different after all? I mean, the F-Log LUTs for X-Trans III and X-Trans IV are clearly different, why are they the same for X-Trans IV and the new X-Trans CMOS 5 HS?
  9. I have an EOS R so it will come eventually. I'm also saving up for an R5C and then I can do something for C-Log3 as well. Yes the packs are tailored for specific cameras, I take about 10k color samples from each camera and from these measurements I create LUTs using my own engine. It's quite a long process.
  10. Ah I see. To create Fujifilm Film Simulation LUTs I need to have the camera for 1-2 weeks, and I don't know a single person in my area who owns it. The other thing is that it takes quite a lot of time for me to create these packs so I mainly go for cameras with large user base. In this regard I'm not sure about the F3.
  11. New ACES IDT packs are released: Leica L-Log/BT.2020 Fujifilm F-Log2/F-Gamut You can get them from here: https://colorizer.net/dev/index.php?op=aces The Fuji one I did almost blindly, I couldn't get my hands on original F-Log2 clips yet, but since the data sheet is already out I created this package anyway. I used youtube framegrabs for verification and I can already see that if you bring F-Log and F-Log2 to the same contrast, the latter has more saturation, especially in the yellow-red area. And greens are a bit more yellow, foliage seems to be warmer.
  12. And nobody here said it's not, yourself included. A little explanation would have helped, as always.
  13. This turned out to be fake, if Fujirumors is to be believed: https://www.fujirumors.com/update-imx671-is-not-the-sensor-of-fujifilm-x-h2s/
  14. Isn't Color Chrome for images only? I don't see how I could enable that for video on my X-T3. My feeling is that the processing is there to hide something, not to enable something.
  15. @tupp nice analysis, I really have to take a look at Darktable again sometime 🙂
  16. Not at all! Do you plan to include info from the Petapixel article as well, or link that article? With the information there my video makes more sense.
  17. Great... I'd rather have an OLPF and slightly less overall resolution than slightly more luma and noticeably less chroma. Or at least they could allow us to modify/switch off the chroma NR.
  18. Unfortunately I won't have the time to test this anytime soon, and I'm not sure it's worth it. The Petapixel artice is absolutely correct about the interpolation issues of the X-Trans pattern, technically there is more guesswork there, and the camera won't have the processing power for a sophisticated demosaicing algo. It's pretty slow even on PC. So I'm sure that the in-camera demosaicing leaves some color artifacts that Fujifilm chose to hide with chroma NR, but they might have gone overkill with that. And I'm surprised that I don't see an improvement on the GFX bodies.
  19. I have access to an X-T3, EOS R, and 5D3. The GFX samples I found online. Did you mean to test with the X-T3?
  20. A last sample, this is from the GFX100s, 4K, 400Mbps, 8bit H.264. It's not F-Log, possibly Provia, so it's chroma channels are supposed to be slightly better compared to F-Log: https://drive.google.com/file/d/1F4W_DYYkYlQIV49lakIGuz1L4xnB3oNm/view?usp=sharing From top to bottom: Original, Cb (with added contrast), Cr (with added contrast) I post this because there are some trees in the background. The theory about this being an X-Trans only issue sounds fine, I might even believe it, but then all the clips that I found from GFX bodies so far tell a different story.
  21. If it's the X-Trans CFA, what's the explanation for the GFX results I posted earlier?
  22. I used ffmpeg first to extract the chroma channels into grayscale videos and I used that to validate the results of my plugin. They were identical so it's safe to say that it's not an NLE/GPU decoder issue.
  23. Another samples, this time from the GFX100, keep in mind that this is 8bit: https://drive.google.com/file/d/1fyCiDFhbkskhjxz2miFgLXn523uP80ns/view?usp=sharing Sequence is the same as before: original, Y, Cb (with added contrast), Cr (with added contrast) This might be the worst I've seen so far.
  24. I don't know guys... just found two GFX100s F-Log clips here (200Mbps 10bit HEVC): https://drive.google.com/drive/folders/1UpKhgQpv8D6pEICjEBvLuAaSTSEvQaHX And here is the result (download please): https://drive.google.com/file/d/1vjFxXTTaqftD8E8GN1vrT5ZTPkaUb6Nq/view?usp=sharing The sequence is the following: original, Y, Cb (with added contrast), Cr (with added contrast) Would be nice to see something more colorful, but I already don't know how this is any better from what we have seen from the X-T3 so far.
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