Adding the 3D Objects reflection to the Movie Item...

I have been messing around with Camera Tracking. It works well. It even adds the Shadow pass. Still the floor is a little reflective. I want to make it more realistic by adding a slight reflection on the Video Floor. I have tried the Reflection pass and searched for a good tutorial but can’t find a single one. If anyone knows a good tutorial on adding reflection of the 3D object to a background image or movie please let me know. Thanks.

Hi Softwarespecial,

I asked the same question a few weeks ago, but nobody seemed to know a good way of doing it. Hope you get it sussed :wink:

Your video is just a background and it will not reflect anything by itself.
You have to create an object that will be 100% reflective (black color is the best) and simply give it the shape of the object from your video.
If it is a floor - simply lay a fully reflective plane on the floor.
This plane will reflect your objects.
In compositor - mix it in using add blending mode, play with Factor etc.
That’s it.
It’s very probable that you’ll need to create another render layer for this.

Another very often used way of doing it when the reflective surface is your floor is to simply duplicate your objects, place copies in another layer and render layer, parent them to empty that’s placed on the floor, scale the empty -1 along Z and you have the reflected objects.
Then it’s just a proper compositing it over your footage.

BartekShorupa First thanks for the responce I know the video won’t reflect I don’t think anyone doesn’t know that. I understand what you are saying but the one problem is there is also a plane that is used for the shadows. That plane messes with the Reflection. I need both Shadows and Reflection. It will need another render layer. The problem is Its the floor and it has the one plane already for the shadows. I need one with the reflections and to have it just show the reflections. The reflection is going to be a slight thing. Since the floor is just shiny enough to give a very low very duffuse reflection. I guess to get to the heart I need to be able to add just the reflection without it messing up with the plane for the shadows. Much like it has a shadow pass it has a reflection pass but I don’t seem to get it to work right. If you have done this before and have a pretty good understanding I suggest if you can make a free tutorial on it. I bet it would be most helpful to quite a lot of people thanks.

Important Note My main thing I need is to simply take just the reflection and make that alpha 1 and everything else alpha 0 problem is when using the reflection node it does the whole plain since the whole thing is reflective. There has got to be some good tutorial out there if not and you have done this stuff before please do make one. Thanks.

BartekShorupa First thanks for the responce I am sure no one would be thinking that the movie can reflect. Any way I Tried it just as you said and it didn’t quite work. I found out a way to make it work. Maybe this is what you meant but any way attached you find under the mirror a function that is highlighted in red the function allows you to control how much of the reflection to show the rest will blend into either sky or material color which you can set note the Green Highlighted area.


By doing what you said and making the material Black and using that feature I was able to get it to work. I didn’t do it with my final video just did a quick test using a random image. I know I can now add the shadow to it as well. Though that will be more work mainly just for me since I have not done that all that much. Any way thanks and Jay Artist if you want to see an example I will be working on it to get things done though if BartekShorupa has one or can explain it better then I. oh and Thanks Daccy saw that just barely

If you set the material to shadeless, it won’t be able to catch shadows. You need to combine the Color, Shadow/AO and Reflection pass in the Compositor, thus excluding the diffuse shading from whatever you’re using as a shadow/reflection catcher.

Daccy I know what you are saying the shadeless was just me testing out the reflection though I have to be honest I was going to try it different but that sounds like it should work much better. Thanks. I will update when I got it working. Thanks again.

Here is how I can get the Reflection to work but now I have had problems with adding the Shadow either I am not doing something right with that aspect which is very likely cause I am not that good at that part yet or it just won’t work combined with this technique. So please if you can get it to work then let me know that hey it works. If you had to do something that is not done in the normal shadow setup then let me know what else is to be done. Thanks and attached is a blend file. This just has the node setup.[ATTACH]172828[/ATTACH]