I’ve been having the same problem with AE and tgas, and also, I’ve done tga secences without problem before. Suddently it started adding this full white to the blue channel.
The solution to me was, like Andy here, Adding the alpha channel to the render.
Maybe it’s a weird bug, and when you set it not to render the alpha, it removes blue channel instead of the alpha inserting the alpha on it.
If anyone knows the real technical problem here, i would like to know =)
thanks everyone!