>I discovered that most of the time for the nopadding case is in the Quintic interpolant setup.

Mike, I'm now worried that the `._rootps_store` cache in the `ImageCorrFunc` isn't being properly used in these tests when the `cf` is passed to the `InterpolatedImage`, otherwise it shouldn't be necessary (as far as I can see) to spend much time in `Quintic` at all when using the `applyNoiseTo` method. 

When you discovered the above, how much information did you get about the calling unit?  (indeed, which tool did you use? I need to learn how to do this...)