Today we are learning a bit more about projections and we will proceed to transform this still image in to a video.
This is the result of the video.
Here we can see the nodes I used. We project a frame hold and we create a Scene to be able to reproject creating a small movement with the camera.
Here we can see it in the 3D viewport.
At the end I used this video to comp a 3D object creating a track with the video I created before. And we can see the result here.
This is also a 3D tracking practice but with this one, we are collaborating with the Maya class to implement and integrate a 3D model that we came up with to after work on the compositing part of the process.
So first is what we have done already to the clip, track it, and create a clean plate of the video. All of this process you can find it in the post about CLEAN PLATES.
While we are creating the patch, we can start modeling what we want to implement in the scene. First, we looked at some references, I chose these images of a steampunk-style machine/motor.
This is where I start modeling it. Here you can see different stages of the process. From the first model to texture and lighting.
After we had the model created we can export the camera and track from nuke to import it in Maya so we can render the model with the right camera and make it move along side the clip.
We also create some shadow catchers to try and match the light from the video we have. As well as some planes with a aishadowmatte material to cast shadows on the walls and floor.
As you can see I have duplicated some of the geometry to fill up more the room.
With all this set up we can proceed to render the model and after import back in to nuke and do the compositing part of the project.
Once in nuke I start to work on the roto for the clip, otherwise, the model would not look like is in the room at the end.
And then we combine both the clip with the model I created for the final result.
This is how it looks at the end.
3D tracking with nuke is a very straightforward process that is used for a lot of techniques like 3D projection, create clean patches of a plate after use it to integrate other models/textures.
Here you can see the original plate that I choose for this practice. I like it because it was an alley with some movement on the back that later can be removed or something. Also, it has a post that passes through right in front of the camera and it would be a good practice to remove it. At least the one thing I’m gonna need to do is rotoscope it out to be able to create patches behind it.
After we denoised the plate and made the right adjustments like some sharpening or grading to make it easier to track, we can proceed to do the track.
As you can see I do some treating before the track, and roto out some areas that could cause some problems.
This is the part the I did the roto were the tracker wont affect.
Then is just a manner of selecting some points and create cards or 3d objects to see that the track is working and also to later work on that to replace it with a patch. Here you can see how the track work. Later on it will be improved and you will see the result at the end.
As you can see in the previous images, we have the roto of the post that I’m putting back on top with a merge node so it passes in front of anything I create behind him. And I also show you the solve of the track, where the purple points selected are the ones that I’m setting as ground points so it knows where the ground is, this will help places patches or anything.
Here I create some patches on the background removing the people to have a clean plate without anyone on it.
The image on the right are the patches to remove the people and the ones on the left are what’s the next step that I’m working on it, remove the close up post that is passing in front of everything with different projections. Here is the end result that I have now.
For the second week, we started to look more at particles and how they work. Using test geometry that we can found in Houdini we created particles that would follow the animation of this object/geometry.
With the node scatter we created points all over the geometry and then delete the ones that we didn’t want to create any particles.
We created a popnet for the popsolver node where we would apply or the forces necessaries for the particles to move the way we want them to move.
After that we copy the particles to spheres and gave it color before merge it with the original model.
For the first week of Houdini, it was only an introduction, getting used to the interface and knowing a bit more about the program and its capabilities, as it was a completely new program for us.
For that we did a rock from a tourus geometry using some nodes like noise and subdivide.
I always wanted to learn Houdini, and to be able to do that as an extra is an incredible opportunity.
Smarts vectors are a way of tracking the image that in some cases makes the job a lot easier if it works properly. We are going to use it for a few practice to learn it, we are going to make a person look younger and also remove some tracker markers from someone.
The first practice is going to be beauty work. I will make a person look younger using smart vectors to track the video and after that, I’m going to create a clean plate that with smart vectors is going to move with the video. Here is the node editor:
We first reformat the plate since it was in 4K and for this exercise, I will work in 1080 then I denoised the plate, and after we create the vectors. This is the first time using this feature so here is how it looks. We can see the vectors on the viewport and the attributes that we can change. I left it to default for now.
I’m going to create the patches with a rotopaint node, using cloning and blur tool. I created a grade node, so its easier to see if the track works well.
Here we can see the difference between the original plate on the left and the modified one on the right.
Here you can see the parts the I modified with the rotopaint:
And here we have the original plate:
This is the end result:
UPDATED AND LONGER VERSION
At this point I modified a little bit the patch I made and also created a few more to make the video longer.
An this is the final result with different passes of the process.