Color Banding when rendering out

When I render at psd(16bit) or png from Dimension I get pretty bad color banding. I started at 300dpi and went down to 72dpi thinking it was a resolution issue, but that didn't help. Strangely in Photoshop the banding isn't really that apparent, unless I'm zoomed out past 67% or until I save it out as a jpeg. What are possible solutions?

Examples above are of jpeg, and photoshop preview:

Anything help appreciated, Thanks.