Well, chances are you may not be working within proper NTSC colorspace. That is the safe color range that can be displayed on a TV or NTSC monitor. There’s a helpful AE tutorial on here that explains that pretty well. Also, your computer monitor may need to be properly calibrated as far as colors go. Just because it looks a specific way on your monitor doesn’t mean that it’s an accurate representation of the actual colors being used. Hope this helps.