When you Render out the clip from After Effect or if you just keep the After Effects project in PPro you can put the Dip to White transition back on. You will get a more natural dip to white look if all the layers ( green screen footage, background and anything else like a vignette) are in one track. If you want the background to always be the same and just have the green screen clip come on and off I would recommend you check out the Ultra Keyer in PPro. It is actually really good.
Stephen Smith
Utah Video Productions
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