Well, I shot a few photos yesterday in the gloomy weather of some birds on the feeders. Here is a photo of a female Pileated Woodpecker shot through my sliding glass door with the following settings:
The noise level is quite low for the conditions and I'm very pleased by that. There is a bit of Luminance Noise, but really no Color noise to speak of in the photo. You can click on the photo to see a larger version of the photo on my Flickr account. I applied no corrections to this photo at all. This is straight off the camera, converted to JPEG and uploaded to Flickr. The largest version (1024x768) shows the result pretty well, although when zoomed to 1:1 on the RAW file, you do see some noise in the background. Either way, I'm still very pleased with my setup!
Additional Comment Added: I realized after making this post that I did have the default Noise Reduction on in Adobe Lightroom which is a setting of Luminance = 0 and Color = 25. After setting the Color to 0, there is more color noise than I initially thought. However, with the default Color Noise reduction of 25, and a Luminance Noise reduction setting of about 45, the noise is knocked down/out and produces a very acceptable photo.