How do you compare Aperture-filtered images with originals?

[tilling]

I'm trying out the demo versions of Neat Image and Noise Ninja on Aperture. In both cases, I can't figure out how to blow up the image and take a close look to see how they compare.
Am I missing something on the screen? I always prefer software that's a bit more self-explanatory...

 

[shoturtle]

Topaz Denoise creates a tiff file once you run it through the plug in. Then you can just compare the original an the tiff in aperture with the eyeloop in the aperture screen or full screen. It seem the simplest one to uses.