7 Replies Latest reply on Jan 10, 2011 7:53 AM by bogiesan-gyyClL

    advice on choosing the right chroma key suit ?

    sherwinetc

      Hi,

       

      I'm in pre-production on a project which makes heavy use of chroma key suits. The tough thing is that I'm shooting it outdoors in bright sunlight. After initial tests with industry standard lime green suits I discovered that they reflect too much light and cannot be easily keyed. Is anyone aware of chroma key suits in alternative, duller fabrics that do not reflect as much light?

       

      This could be an option:

      http://www.milanoo.com/Fuchsia-Red-Unisex-Lace-Zentai-Suit-p16069.html

       

      And yes, I am aware that these things are built for something other than chroma keying!

       

      If anyone has any ideas, I'd love to hear them.

       

      Cheers,

      Sherwin

        • 1. Re: advice on choosing the right chroma key suit ?
          Mylenium Most Valuable Participant

          And yes, I am aware that these things are built for something other than chroma keying!

           

          No need to feel awkward and apologize. It's no doubt an option. The question is, what suits you have investigated so far. For the most part it's a problem of what materials are being used. Synthetics always have a lot of glossiness to them, so you might just need find a variant consisting of mostly cotton with a hint of Elasthane. Perhaps you can get that from ballet clothing manufacturers or professional costume designers for theaters and otehr performing arts. also consider, that because of the thinness of the cloth it wouzld be perfectly possible to wear a black suit underneath any otehr color to make it appear darker and absorb a bit more light. Naturally, you may still need to pick a darker green or blue to begin with. and of course full body makeup might be an option, if e.g. you only have the upper body of the riggers/ assistants/ stand-ins/ whatever in frame - a snugly fitting Tee and the arms and face painted over would then suffice. It may just become inefficient if you have to apply it on multiple performers on many days of shooting...

           

          Mylenium

          1 person found this helpful
          • 2. Re: advice on choosing the right chroma key suit ?
            sherwinetc Level 1

            Hi Mylenium,

             

            Thanks for the detailed response. Appreciate it. I've been looking into fabrics and have found some 95% cotton 5% spandex that's quite dull and I think will do the job. It's available in magenta and red amongst other colours. My location is primarily made up of green and gold plants and dark brown dirt so magenta seemed the best option for the suits. What do you think about this? I'm also aware that a primary colour like red may be easier to key out but I'm afraid of clashes with reddish brown dirt and golden grass...

             

            Oh, I didn't quite understand your statement: 'Naturally, you may still need to pick a darker green or blue to begin with'.

             

            All the best,

            Sherwin

            • 3. Re: advice on choosing the right chroma key suit ?
              Mylenium Most Valuable Participant

              If it doesn't wreak havoc whith your skin tones when keying, then red is fine. A dark burgundy or purple should not cause too much trouble and provide enough contrast, assuming you don't have much other reds in the foreground. If it's in the budget, you might still consider getting a green or blue suit as a fallback plan... You never know when some red poppys or tulips might be in frame . And of course keep an eye out on anything you can do on set with lights, putting cardboard masks on the camera itself to hide stuff in static shots or using lens filters to shift colors around and possibly recover them in post...

               

              Mylenium

              • 4. Re: advice on choosing the right chroma key suit ?
                bogiesan-gyyClL Level 3

                I don't have anything to offer yet but I'm curious why you're using chromakey suits in a natural environment. Pre-production is where you plan so you don't waste effort and money but I don't see why you'd need to make people disappear out of the scene. You don't need to explain your project if you think it's proprietary but I'm imagining a wide variety of terrible things that can go horribly wrong. For instance, in an outdoor setting, stuff behind the person in the suit must be replaced by a clean plate. Are you replacing the suits with something like CG characters? Does the replacement need motion control or motion capture? Do the people in the suits handle objects so they appear to move by themselves? You will need handles on those objects so the suit does not occlude the surfaces of the objects. There are people here who have either solved all such problems or been on sets where they've been solved or who can help you research practical solutions.

                 

                Good luck with your project.

                 

                bogiesan

                1 person found this helpful
                • 5. Re: advice on choosing the right chroma key suit ?
                  sherwinetc Level 1

                  Mylenium, good to hear some positivity about the use of reddish coloured suits. I'm still not sure whether pink or red is the best option, but i suppose test shoots will clarify that. I do already have some lime green suits that will be my backup. Putting a mask directly onto the camera could be a good problem solver - will definitely remember that one.

                   

                  Bogiesan, to explain the project briefly, I am animating the character's bodies with various imagery but often the silhouettes are filled by the defocused image of their background - as if their bodies behave like a prism that defocuses what we see through it. For this imagery, I'll shoot a defocused clean plate after every take. Here's a slap-dash shoddy example of the effect:

                   

                  defocused test image.jpg

                   

                  The easiest way to make sure the defocused footage matches up with the alpha footage (ie. in the example above, that the difference sections of the white path line up) is to keep both shots static on a tripod but as I'd prefer a handheld feel so I'm experimenting with motion tracking options. My idea is to shoot the takes with the suits handheld and motion track the movements in post, shoot the defocused clean plate on a tripod and attach it to the tracked motion so that things vaguely match. I figure that with defocused image, I do have some margin for error since lines are blurry and due to the nature of lens optics, things move within the frame when you pull focus so it is impossible for them to match up exactly. My main question is whether I need to place markers on my actors or the background to facilitate motion tracking. Once chroma keyed, wouldn't the the silhouette provide a sharp enough point somewhere to motion track off? The sensible option is probably to place a bold coloured marker on my actor (ie. hot pink if he's wearing a lime green suit) and key both out with seperate filters.

                   

                  The figures will be handling objects like rocks and sticks and it's going to be a complicated matter of shooting defocused images of the objects (ie stick) and matteing them in where appropriate (ie. through the figures hand).

                   

                  I'm sure you envisage problems so i'd love to hear about them!

                   

                  Cheers,

                  Sherwin

                  • 6. Re: advice on choosing the right chroma key suit ?
                    sherwinetc Level 1

                    Ooops, my mistake - any motion tracking points would have to be on a static element (eg a tree) rather than on the actor. I want to track the movements of the camera not the actor! You get the idea..

                    • 7. Re: advice on choosing the right chroma key suit ?
                      bogiesan-gyyClL Level 3

                      > The easiest way to make sure the defocused footage matches up with the alpha footage (ie. in the example above, that the difference sections of the white path line up) is to keep both shots static on a tripod but as I'd prefer a handheld feel so I'm experimenting with motion tracking options. My idea is to shoot the takes with the suits handheld and motion track the movements in post, shoot the defocused clean plate on a tripod and attach it to the tracked motion so that things vaguely match. <

                       

                      Thanks for the explanations, sounds like a ton of fun. Wish you every success.

                       

                      The handheld factor can be added in post if you have the resolution top allow for a bit of scaling. You can impose movement to the clip to simulate handheld Best way to do that is to shoot some handheld footage including some markers, track the markers, apply the motion to the video. This adds real world camer movement instead of a set of keyframes which always looks fake.

                       

                      You sell the effect by animating a separate foreground layer so you have some paralax. Not easy but fun.

                       

                      bogiesan