I had a project a few months ago that required projection and I had to manually adjust the aspect ratio numbers until it fit perfectly. This would've been so helpful. Thank you so much! Great tutorial!
We are very aware of the effort you have put in, as a community. However, I have a request, which I'm sure other friends would also want. There should be a way to use the shadow catcher of the Octane render engine as a reflection catcher as well, without being confined to the layer ID. If you find a way, please share it with us. It becomes essential in projects where adding a 3D object to a video is crucial.
Not very artist friendly, but I suppose once you set this up you can keep it pretty much as a preset. Thanks for this, been wanting to explore this further.
hmmm, not sure what I'm doing wrong but the FOV math didn't work out for me like this. I followed the steps, and the the projection was correct-- but too small. I had to multiply the math you laid out by an additional 1.43x. So not sure where that comes from. Project size and images all match. I'll keep looking into it.
Thank you very much for your comment. Maybe they changed something until back then... 🤔 If I have the time I might look into it again. At least you got there somehow in the end 😇
@@SilverwingVFXYep, thanks for the reply! I'll try a totally new project and see what happens in that. I'm using camera data from pftrack, so maybe that introduced some kind of scaling issue? I be sure to comment again when I figure it out.
How would you use this to project textures from live action plate footage so the environment has correct scene. Diffuse or emission texture? Also, how would you then setup the projected textures as shadow catcher as well to get realistic shadows and reflections?
Hey there and thank you very much for your question. I think this is a bit complicated since you want to use the image to affect the object in the reflection / refraction and also diffuse lighting. If it would just be about the emission and not the Shadow Catching aspect of it, I would use pure emission with it. Set a diffuse material with black diffuse, then use a "Texture Emission" with "Surface Brightness" ticked on. Though this then would not catch shadows and reflections. So you could experiment with also using the same image on the diffuse and then, depending on the material of the projected object also add a reflection. This is only possible with the universal material. Since the Diffuse Material does not have a reflection and the Glossy Material does not have emission. So you could make a universal material with e.g. a glossy reflection and a projected texture, that goes into the color (Albedo) and emission. If you are OK with just a Shadow as well as the Diffuse GI of the Object, stick with the Diffuse Material. Then use the render layers to get your object-, it's shadow and it's reflection separated and on its own render pass / render layer. This can be merged in compositing (like After Effects, Nuke or Fusion Studio) or within octanes own internal compositing context. I have videos on all of those: Render Layer & External Comp in After Effects: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-YB4LBf_t_Xs.html Render Layer & Internal Comp: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-bEgjnyNwOSg.html New Internal Compositing Nodes (This might be necessary to know what to do in newer Octane versions): ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-ULrxD_7fJKs.html Basically you would use your video as an background layer (like what I do in the second video with the gray background) Hope this all makes sense and helps. If you have questions, then feel free to ask
Thanks for this. Can you explain how the original method wouldn’t work for some VFX shots? What would be the reason for using the octane camera baking in VFX?
Hey there. Yes, of course. There are situations where you need to bake down your projection to objects that have existing UV sets. Mostly if you want to deform your projection. Think about a birds eye view video out of a helicopter that you tracked and now reprojected to a ground plane. If you want to simulate a meteor hit the ground plane would deform from the impact. With both the C4D and the Octane method your projection would still look as if it was flat and not follow the mesh. With C4D you are using the UVs for your projection. They are different each frame of the video, because your viewing angle changes. With Octane the projektion is done Procedurally so you are free to bake down the animation to the existing ground UVs. After that you just have a UV mapped moving texture on your object. So you can deform your object and the texture (former projection) will deform with it. Sorry for the long read. I hope that makes stuff a little clearer. Cheers and an awesome Day to you!
@@SilverwingVFX Thanks so much for your thorough explanation. Your videos and tutorials are actually very helpful and needed. You touch upon a lot of things in cinema 4d and octane that we can't find on the internet. I hope you continue making more!
Thank you very much for your comment. What would be the intended result for you? Eventually setting the "Border Mode" U and V to something else then "Wrap Around" in your input texture node will help 🤔
Hey there and thank you for the comment. Sample Position to UVs won´t show up in reflections / refractions etc. correctly. It will never reflect / refract the right part and always show the part of the background image that would be at the reflections / refractions UV location, not the position the ray is actually traveling.
If you are reffering to the green screen part yes! Go look up this on RU-vid: Siggraph 2018 Rewind Aaron Sorensen: VFX & Compositing with Redshift & C4D. He shows Ians workflow but just in C4D :)
I would have to look at how exactly he is modeling. But I guess something like this can be done. However I think it would be more in the side of projecting then converting to UVs, like the 1st method I showed. I do the conversion from the tags to UVs just to make it more understandable. But this can be also used to fixate the projected textures.
Hey there. You have to bake the Projection to the UVs. You can do that using this technique: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-gcJNWtI7ouc.html You need the Octane Native Camera Projection method and good UVs on the geometry you are projecting on. Just bake the Texture and reapply it as a UV mapped tex. Unfortunately there is no internal way of doing it on the fly. At least that I know of! Hope that helps 🙂
