7 Replies Latest reply: Apr 28, 2013 3:26 PM by wolvesjim RSS

    Color correction query

    wolvesjim

      Hi There,

      Following gaining a successful resolution to this issue using the 'Screen' mode of the Opacity function, I have now encountered a slightly different issue. Having layered multiple frames, I am experiencing an awful lot of what I think you might call 'noise'. The more I layer the frames of black, the more I lose the pure nice black colour of the night sky and it becomes lighter and more blurry and grey. Is there a color correction or other such function or technique that might eliminate that noise and maintain the clean black color?

      Many thanks,

      Jim, U.K.

        • 1. Re: Color correction query
          JSS1138 Community Member

          I'll be honest, I don't have a full grasp on what it is you're trying to do here.  Some screen shots might help.

          • 2. Re: Color correction query
            wolvesjim Community Member

            Hi Jim,

            Thanks for taking the time. I'll try to explain. So I took a continuous frame of some lights in the dark on the skyline that looked like this...

            Capture.JPG

             

            The frame moves around so they're in a different position on the screen, so I chopped it up and isolated those moments before layering a few frames and adding 'Screen' opacity to it. Effectively therefore the lights appear numerous times in the frame. Here's one of about 5 layers...

             

            Capture1.JPG

             

            Effectively I wish to have these lights all fan out and fill the screen but as you can see the image is becoming grainier and grainier the more I layer and nest the frames. Here's what it looks like after 10...

             

            Capture2.JPG

             

            Not pretty I'm sure you'll agree. I hope you can see what I'm trying to do though. I'm no expert but presumably there is some sort of technical term for the way that the multiple layers of black are obscuring the quality of the image. It's not your average difficulty I admit but if you know of any method by which the body of the image can be restored to that nice dark black whilst the lights remain clear and sharp then you would rescue me from an ongoing frenzied Googling session.

            Kind regards,

            Jim W., U.K.

            • 3. Re: Color correction query
              joe bloe premiere Community Member

              You should do this in After Effects using a key

              instead of 'screen' blending in Premiere.

               

              Here is 10 layers 'Luma Keyed' on top of each other in Ae.

              (I downloaded your first image for this comp)

              AeLumaKey.png

               

              You can also use the free Red Giant 'Unmult' plugin for luma keys:

              http://www.redgiant.com/products/all/knoll-unmult-free/compatibility/

              • 4. Re: Color correction query
                Fuzzy Barsik Community Member

                So as to understand how each blending mode works, see this help section.

                 

                Back to your goal. In your previous thread you was already proposed to use Luma Key. You can definitely try to accomplish your task in PrPro. However, as Joe points out, you're better off with After Effects, 'cos it is a compositor and, hence, designed to do multiple layered compositing much more convenient.

                • 5. Re: Color correction query
                  JSS1138 Community Member

                  You should do this in After Effects using a key instead of 'screen' blending in Premiere.

                   

                  I agree, except use the UnMult plug-in from Red Giant.  It's free and get's rid of 'black' real good.

                   

                  http://www.redgiant.com/products/all/knoll-unmult-free/

                  • 6. Re: Color correction query
                    wolvesjim Community Member

                    Hi Joe,

                    Thanks very much for your advice. Looks like I'm gonna have to get to grips with AE. In the process of learning- any chance you you could give me a quick explanation of how you created that layering effect?-just a briefly outline of the processes I should be trying to learn..?

                    Also I downloaded Unmult and copied it into the effects folder but its not showing up when I search my Effects- what have I done wrong? Is that the correct way to import effects?

                    Thanks again,

                    Regards,

                    Jim.

                    • 7. Re: Color correction query
                      joe bloe premiere Community Member

                      Looks like I'm gonna have to get to grips with AE.

                      This stuff will help get you started:

                      After Effects Help / Creating layers

                      After Effects / Keying effects

                      Understanding Luma Keys

                       

                      Basically, what I did to create the above image:

                      Imported your still from post #2 to Ae.

                      Created a new composition from the still.

                      Duplicated the layer, added a luma key, offset slightly.

                      Duplicated and offset the keyed layer 9 more times.

                      I downloaded Unmult and copied it into the effects folder but its not showing up when I search my Effects- what have I done wrong?

                      Install:

                      C:\Program Files\Adobe\Adobe After Effects CS6\Support Files\Plug-ins

                      or

                      C:\Program Files\Adobe\Common\Plug-ins\CS6\MediaCore

                      Both work for Ae.

                      You should find it here:

                      unmult.png