I am not good at using a gradient mesh in illustrator or core draw (any vector program), it makes sense to create a non linear complex gradient in Photoshop. However when using tools like live trace I get a banding problem where each part of the gradient is split up into individual parts. How would I convert the bitmap into a one piece gradient vector mesh, I use Corel Draw and Illustrator. Would not be opposed to using a standalone tool. The problem is that you’re trying to go from apples to oranges – the gradient in Corel Draw / Photoshop is a raster image, and you’re trying to then bring it in and apply it as a vector gradient. A raster gradient has a defined size, and attempting to map it using the live trace tool causes Illustrator to try and find specific values at specific points within the gradient – thus the ‘stepped’ result. If you’re greatly expanding the raster shape you’ll also be dealing with jaggies and aliasing artifacts from rescaling a raster gradient. Source.