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  • #91
    I was testing out a new rig and shot my son running around outside, he was wearing a grey sweatshirt and when I looked at the ProRes I also noticed a nasty red/green chroma noise pattern on his top. Thought it may have been my Camera as I've ony had it a fewdays and haven't had a chance to play with it but it appeared isolated to his top. The texture of the material was nothing special and I was a bit confused by the outcome.

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    • #92
      Need Help with Nodes and Windows

      Thanks to Paul DelVecchio's great resource for chroma noise reduction ( http://www.youtube.com/watch?v=degEMVPLPdU ) things are looking cleaner.

      What I'm trying to figure out's this: how do you use Paul's Node Tree but modify it to where you're able to track a power window with the chroma noise reduction applied to it. Say if you were trying to do one quarter of the screen or a noisy face for whatever reason.

      Been trying and searching for a few hours and last night as well, no luck.

      Any help would be appreciated!

      SKYPE (best way to talk to me): Camera_Kholi | twitter
      Avery and Pete: Superseeds Feature Film Trailer

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      • #93
        Kholi, I was doing the same thing two days ago, if I understand you correctly. I was tracking someone's hat that showed a lot of moire. I didn't want to apply the aggressive color blur to the whole frame, but just the hat.

        What I wanted to do, but I never figured out, was to have the same tracked power window on both the luma and chroma nodes. But, I couldn't figure out how to get them to be identical. I seem to recall reading that this might be an upcoming feature of Resolve 10 (the ability to copy tracked mattes/windows from one node to another - but I could be wrong).

        My workaround that seemed to work was as follows.
        1. Create the layer nodes as in Paul's video.
        2. Apply the power/tracking window on the chroma node and add your blur or noise reduction to the object. This will look wrong, as all but the power window area will be black and white. That's okay, we'll address this in the next step.
        3. While on the chroma node, add a serial node. Then, adjust this node to also be chroma only (i.e., remove the luma). This should result in having two chroma nodes (in series) that get combined with the luma node in the layer node. I apply a little blur to the second chroma node, too. I've found that the BMCC footage usually benefits from a little chroma blur.

        That worked for me, I think. Hopefully this works for what you are trying to do, too.
        Last edited by Jason Greene; 05-16-2013, 08:35 AM.

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        • #94
          That did it.

          And, that's exactly why I went looking into it. I'm gonna combine this thread with the other one because I think this is a pretty solid way to get rid of moire for now. It won't deal with the aliasing, but for the rainbows?

          Lookin' a ton better.

          SKYPE (best way to talk to me): Camera_Kholi | twitter
          Avery and Pete: Superseeds Feature Film Trailer

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          • #95
            And here are some examples from a quick shoot like two weeks ago (click image for 1080 jpegs to see the difference):

            Picture 1: Before



            Picture 1: After (just the power window used to kill the color moire)


            Picture 2: Before


            Picture 2: After (power window)


            Picture 2: All chroma noise reduced


            Notice how the face loses some life. You can get it close, but I could never really get it back to the original, which appeared to look much more life like in comparison.


            It isn't a perfect fix because you have to add some steps in post, and you kind of take a hit on color where you're removing the moire, but it is a large relief for me that this is even possible until we have better solutions. Being able to show this to my colorist so that they can work it into the workflow, and start teaching others, is going to be a very big help.

            WE've had to do worse to fix RED footage, canon footage, etc.

            Thanks a ton, Jason. And thanks to Paul for the initial method that brought this about.

            SKYPE (best way to talk to me): Camera_Kholi | twitter
            Avery and Pete: Superseeds Feature Film Trailer

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            • #96
              Awesome! Glad this worked out. Of course, when Resolve 10 comes out, we can use Neat Video to play around with the Chroma and Luma noise reduction as we wish. I think I'm going to try Neat Video and see how it removes the rainbow moire. Having Neat Video in Resolve is going to be such a great addition to the tool.
              Paul Del Vecchio - Director/Producer
              http://www.PaulDV.net
              https://vimeo.com/channels/directorpauldv
              http://www.youtube.com/user/pdelvecchio814
              http://www.twitter.com/pauldv

              https://www.facebook.com/pages/Paul-...io/58731646898

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              • #97
                I'm glad that worked for you. Looks great, Kholi. Yes, the targeted chroma blur works well and leaves the chroma detail in the face.

                Out of curiosity, what level of blur did you have to use on the shirt?

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                • #98
                  Originally posted by Jason Greene View Post
                  I'm glad that worked for you. Looks great, Kholi. Yes, the targeted chroma blur works well and leaves the chroma detail in the face.

                  Out of curiosity, what level of blur did you have to use on the shirt?
                  I actually didn't use any blur on the shirt, I just shot NR removal up to 6 I believe and that removed the chroma. I think mist or blur and a combination of NR would be a better combo, though. Will have to try that.

                  SKYPE (best way to talk to me): Camera_Kholi | twitter
                  Avery and Pete: Superseeds Feature Film Trailer

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                  • #99
                    Yep, i've been doing what Jason said too. I also sometimes do a "windowed" sharpen node on the luma path too. This will be easier in R10 with the new Splitter Nodes etc. The only thing i can really add relates to this:

                    Originally posted by Jason Greene View Post
                    What I wanted to do, but I never figured out, was to have the same tracked power window on both the luma and chroma nodes. But, I couldn't figure out how to get them to be identical. I seem to recall reading that this might be an upcoming feature of Resolve 10 (the ability to copy tracked mattes/windows from one node to another - but I could be wrong).
                    How i've dealt with this is the following, grab the little blue triangle on the right side (output) of the node with your tracked power window and connect it into the blue triangle on the left (input) side of your target node, then in your target node go into the key tab and invert the input key. Node tree looks like this:

                    Blackmagic Design
                    My BMD LUTs.

                    **Any post by me prior to Aug 2014 was before i started working for Blackmagic**

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                    • I've yet to delve into Resolve but I'm really hoping that v10 comes with a really straightforward process to reduce the occasional ugly moire that seems to be the biggest weakness of the BMCC. Also be interesting to see how much of an issue moire is on the new Pocket and 4K cams.

                      Thanks Kholi for starting this enlightening and occasionally confusing thread.

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                      • J.F.R, this post is with reference to the Rodney Charters thread, and thought I would post in here to stay on the moire topic I wish to discuss further with you and other members, and perhaps revive in this thread. I do not currently use Resolve as my main post colour and grading tool/app, and perhaps you may be in a similar situation to me, so perhaps this thread is not the right place to ask you about your experience with moire and how you deal with it in post, if at all?

                        I have watched some of your music productions, great looking content and post colour work. Have you used the 5D on client based music projects and encountered the moire issue in your shots, and if so, have you abandoned the shot, or fixed it in post? If a post fix, care to share any techniques? If Resolve is not your app of choice, perhaps we may need to take this discussion to another area in the forum. I am not currently using Resolve other than slowly getting familiar with the Lite version, and I prefer to work from within my Premiere, and limited use of AE. I have a licence for Neat in Premiere, which provides a possible method to try and tame moire, as discussed and samples presented in this thread.

                        I am also curious if filters to some extent do what an OLPF can do? I have not seen any tests to use an alternate filter to an OLPF to try and tame moire. I am not suggesting front filter will do a similar job to a specific filter like the OLPF at the end of the optics chain. CaptainHook has the GlimmerGlass 1 (GG1) which may help moire in some situations? I am sold on grabbing a GG1 to add to my filter kit. I went to order a GG1 in 82mm, to match my run and gun filter set, and the anticipated wait was about 10 weeks. I did not order it, instead purchasing the things I needed for the BMPCC. GG1 is not a popular build in 82mm. I will purchase a GG1 if the BMPC 4K does not appeal to me when I see some sample footage, and then purchase the BMCC in MFT. I have various 4x4 diffusion type filters also, however, since I don't have a 5D or BMCC, I can't really test specifically for attempting to tame moire. J.F.R, I am interested to hear some of your feedback regarding dealing with moire issues in footage that you may encounter when using a camera like the 5D in your music video productions? Thank you.

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                        • When i next get time, i will try induce moire on the BMCC/EF and then do a comparison with and without the GG1 so you can see if it's something you'd be interested in. Otherwise i suggest trying to rent one if possible (i could not find one to rent here in NZ ).
                          Blackmagic Design
                          My BMD LUTs.

                          **Any post by me prior to Aug 2014 was before i started working for Blackmagic**

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                          • Thanks for chiming in, CaptainHook. I should have just ordered the GG1 when I placed the order for various items from B&H, not realising after that I could have split the shipping and have the GG1 sent later, perhaps 10 weeks or so later. I did not want to have all the other items in the order held up. I got the order wrong. I will order next time, and do split shipment. Interested to see any test you may care to do with the BMCC naked (with perhaps ND/IRND filters), and then with the GG1, and any other diffusion type filters you have in your kit (promist, etc), aiming at a problematic moire shot.

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                            • Originally posted by PaulDelVecchio View Post
                              Awesome! Glad this worked out. Of course, when Resolve 10 comes out, we can use Neat Video to play around with the Chroma and Luma noise reduction as we wish. I think I'm going to try Neat Video and see how it removes the rainbow moire. Having Neat Video in Resolve is going to be such a great addition to the tool.
                              hey Paul, now that Resolve 10 is out and NR is done differently, how do you go about reducing chroma noise/moire?

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                              • Originally posted by django View Post
                                hey Paul, now that Resolve 10 is out and NR is done differently, how do you go about reducing chroma noise/moire?
                                I tried the new noise reduction honestly, I feel the old method is still better. The new one, I felt I had to increase it so much that it just blurred the colors so much and it started looking messy. I also like using Neat Video and it actually is what I use most of the time.
                                Paul Del Vecchio - Director/Producer
                                http://www.PaulDV.net
                                https://vimeo.com/channels/directorpauldv
                                http://www.youtube.com/user/pdelvecchio814
                                http://www.twitter.com/pauldv

                                https://www.facebook.com/pages/Paul-...io/58731646898

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