I'm using Illustrator CS6 on a PC. In the past I've used Gaussian blur to create a blurred smooth transition between two colours (see 1st image) and that worked fine if the shapes are on the same layer and all selected together when blurring. I now have the need to have the different colours on different layers, this results in the whiteish halo effect between the blurs (see 2nd image). I understand what Illustrator is doing when using the Photoshop effects, I'm just wondering if there is an easy workaround to get rid of the whiteish halo. Any thought?
I did try adding a stroke of the same colour to the shapes but then the ordering of the layers becomes important so that you don't lose some of the small areas.