Using Low-Res 3D Renders in After Effects Before Final Render

[lucash81190098]

Hi everyone,

I'm a 3D artist, and my workflow involves rendering 3D layers from Blender and compositing them in After Effects. Since 3D rendering can be very time-consuming, I’d like to set up my compositing using lower-resolution versions of my renders first. This way, I can identify any issues before committing to a full-resolution render.

What’s the best way to properly manage this in After Effects?

1. I know you can manually resize layers and compositions, but this can be unintuitive—especially when dealing with nested compositions. 

2. I’m aware of the proxy system, but my challenge is that the final high-resolution version doesn’t exist yet. Since the whole point of using a low-resolution version is to preview the composition before rendering at full resolution.

Does anyone have a recommended workflow or best practices for handling this? Any insights would be greatly appreciated!

[ShiveringCactus]

If you have everything set up with your lower res images, from the project panel, you can hold ALT and drag your high res version either onto the image in the project panel to replace all OR onto each in copy in each comp.  The only issue you might still face is the size/scale of the images.  But if you had the image only appear once in a nested comp, that would mean you'd only be re-scaling once.

[Warren Heaton]

Before importing the low-resolution version, create a duplicate in Finder or Explorer and change the Image Size in Photoshop to match the full-resolution version. Append something like “_upconvert” to the end of the file name.

Import the version with the adjusted Image Size (the _upconvert) and set the low-resolution version as the Proxy.

When the full-resolution version is available, use File > Replace Footage to swap the _upconvert version for the full-resolution version; you can leave the Proxy enabled or remove it.

This assumes the low-resolution version has a smaller image size than the full-resolution version.

Another approach is to use After Effects’ placeholder feature to create a full-resolution placeholder, set a Proxy, and replace the placeholder with the full-resolution source footage when available.

[lucash81190098]

Hey Warre, thanks for the reply!

I appreciate the suggestions. My situation is a bit more complex, so I'll try to provide more details.

If each of my render layers were just a single image sequence, I could simply drop them into my main composition, replace them with the high-res versions when ready, and adjust their scale accordingly.

However, I’m working with Multi-EXR image sequences, which contain multiple layers (diffuse, gloss, transparency, etc.). These sequences need to be assembled into compositions in After Effects before being added to the main composition. Because of this, I’m unsure if compositions can be replaced as easily as regular footage.

The main challenge is that when I swap the low-res EXR sequences with the high-res versions, the images become scaled out of bounds within their individual compositions. This means I have to manually adjust the composition resolution for each render layer. On top of that, I also need to adjust the pre-comps inside the main composition, making the process even more tedious.