Hi, I'm completly newbie in After Effects, my development flow is growing fast, but I have been problems with high definition encoding, I'm rendering the movie in lossless avi and after that converting to h264 in Adobe Media Encoder, but my gradients are streaked always, someone can help with it please?
what you're seeing is commonly called 'banding' and can usually be fixed (or at least lessened) by increasing the bit-depth (set ae to process in 16 or 32 bits per channel) and/or adding noise to the render.
if you are seeing banding in the lossless/uncompressed output from ae, then setting ae to render at 16 or 32 bpc may help.
if the banding is only happening after compression, or you want to keep rendering in 8 bpc, then adding noise to the render should help. you can do this in your comp by creating an adjustment layer and adding the noise effect with a little noise until the banding goes away. if the banding isn't present in the comp preview (since it may occur after compression), try adding around 2% and see how that looks after compression.