Poser 12 Denoising Filter creates two images, the denoised one and the original with noise. So far so good. For still images this is not an issue, but what about Animations? I made an 180 frame Animation and used the denoiser, so the image folder contains 360 Pictures. The originals are useless, I delete them manually each time. Is there a setting to avoid that the original Pictures get saved?

Probably there is no setting to avoid the Originals.
But if it'll help ease your mind, imagine animating 3,121 frames, with the background being separate from two foreground layers. After a while you're like: meh, originals. Lett-em stay. They actually come in handy to blend between the original, and the denoised version which tends to be too blurry.

Don't look at it as a hindrance, but instead look at it as an unexplored opportunity.