The following were derived from a 50D image taken at ISO 3200, -1EV (because I was trying to dim the candlelights), f/4, 1/2 second handheld with IS on. Click on any thumbnail to enlarge.
1. Image after ACR and Neat Image Noise Reducer, reduced for display here.
2. Crop of ACR conversion.
3. Crop of DPP conversion.
4 Crop of DPP conversion after Neat Image Noise Reducer. Compare with 5.