How mutch faster  C4D renders depends on what your image contains. The longer Poser needs to render, the bigger is the difference because C4D's renderengine works with a lot of professional tricks to make complicated things fast. Twice as fast should be no problem (with mutch higher quality compared to Poser). I just did a render in Poser that needs half an hour. In Cinema 4D it needs just 5 minutes and has better quality.

If you use the plugin InterPoserPro you are able to import characters and props from Poser without the need to re-rig. Morphs done for Poser are also usable in Cinema 4D. Simply load a Poser scene into C4D and you are able to do nearly anything you can do in Poser. I'm actually using the demo version and will buy this great tool as soon as possible.

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