Alpha Channel on Texture Creates Odd Aliasing Effects


#1

Observe the following image:


Now observe this one:

The only difference between the two is that the second image has four planes in front of the colored stripes. Each plane has an animated texture of moving dots on it, and those dots are being used as an alpha channel so you can see through to the objects on the other side of the plane.

The problem is that when I use the alpha channel, it makes the stripes behind the planes look terrible. I have no idea why this is happening and have tried playing around with all of the alpha channel settings and have no idea how to make this problem go away. Increasing the anti-aliasing in the render settings also didn’t really help.

I have attached my project file below so you can see this problem firsthand. Please let me know if you have any idea how to fix it. I’m using R19. Thank you.

Alpha c4d problem aliasing.zip (40.4 MB)


#2

Change Min & Max Samples to 16x16 and Anti-aliasing to Best
The Alpha is to blame. Try putting a simple cube behind your planes, you’ll see it pixelized.


#3

While that does solve the problem, it obviously will have a huge impact on render times. Do you have any other suggestions?


#4

Increase the min-value step by step until it looks good. do not use the same value for min and max.
did you try physical render?


#5

Unfortunately no.

That’s the only way I could remedy your scene without changing the approach of your scene.

If I was having the exact same problem I would try having the same effect using disc clones instead of the texture animation… It’s going to get heavy in polygons … maybe use some mirrors with a compositing tag I don’t know. Scene was already heavy for me to play the animation in the viewport and I couldn’t understand why. I didn’t try to reverse engineer it cause I had to solve the particular problem.

Have you tried converting those texture frames to jpg ? It seems weird that the alpha behaves that way. I have encountered the same problem in the past but it didn’t bother me because the effect didn’t appear so much on the screen.