Here are two videos, which demo Rich-capture and 4K video capture on a Lumia 930, updated to Lumia Denim. The video maker has also posted before-after DNG (RAW) images and with and without Rich-capture (Auto HDR and Dynamic Flash) scenarios.
Coming to the comparison results, the Rich-capture certainly provides images with better exposure as compared to those with Cyan and one can notice more details and clarity in DNG images captured by Lumia 930 running Lumia Denim. Read more about the imaging improvements Lumia Denim brings for Lumia 930, Lumia 1520, Lumia Icon and Lumia 830 with Lumia Camera 5. Other devices won’t get the improvements, though.