"my point was that if someone is pushing the boundaries of poser and starting to hit the limits of the poser renderer, i can understand them wanting to render in another renderer."

And hitting the limit of posers rendering power will happen the very moment you become serious about rendering Animation with actual 3D Environments with  Characters interacting dynamicly with their environments
SAMPLE

or rendering flicker free GI/ IDL
within your lifetime
SAMPLE

Both video samplesl are C4D AR3 BTW

"but there are very few people pushing the boundaries. and if youre not, switching to C4D is as likely to make your renders look worse as it is to make them better."

I am a render engine Junkie ..I admit this freely.

I have access to the Following render engines (although not the latest versions) :
Smith micro-Poser 6 (never use except to previs
character animation to check for errors)

Daz studio 2.3.6 "3D delight*( never used as it crashes immediately when I hit render on OSX)*

Maxon Cinema4D R11 Studio- internal AR3
Chaos Group- Vray for Cinema4D
Luxology- MODO 401
Newtek -Lightwave 3D 9.6 internal
MindBerry Kray-2 for Lightwave 9.6
Nextlimit- Maxwell 1.7
Eon-Vue 6
Blender -2.5 internal.

Now I must be blunt and this is not to disparage poser users for what they choose to render and post online.
Excluding Daz studio I could take the time to cook myself up a very nice SSS skin shaders in blenders node based shader system
lightwaves node based shader system
or MODO's excellent  &fast SSS solutions or anyone of the above mentioned engines.

Import naked or bikini /clad V-chick
place camera set lighting GI or standard
render,post to web gallery
So what!!.. in the end its just another naked poser chick Except that you have spent way more money to  acheive that same boring objective as some poor fellow who can only afford poser 9.

So if the majority of one srenders are doing Semi naked/naked people just sitting still in a largely empty universe then switching to C4D,Vray  etc etc even with Good SSS& hair etc solutions
and continuing to produce such renders is an utterly pointless exercise IMHO no matter the speed increases.

Cheers

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