Which one is better?
In terms of realistic scenes.
Compared to what? BI?
You can use PRman to render scenes out of Blender, assuming one of the renderman exporters is up to snuff for your project.
Have you looked at the price of PRMan heart attack inducing.
You know, I hate to say it but… that is kind of an amusing question (really, no offence). I’ll let you decide for yourself. Take a look at this page: RenderMan Movies
J_the_Ninja is right though, you can use Renderman if the exporter available. I think it is called RIB Mosaic.
Bye the way, you do know that Renderman is just a renderer right (not to mention $$$$)? Kind of sounds like you think it is a general 3d app. I am assuming that you were comparing it to BI though. 
yeah, that’s a good question, are you referring to BI or Cycles? renderman-compliant renderers offer much more realistic DoF than BI, and really fast motion blur. displacements are easier and faster to render than in BI, so you can render more ‘realistic’ objects with displacements with shorter render times and less CPU strain.
but you have to do a lot of ‘cheating’ with most of these renderers too, and there’s generally a whole lot of pass and shader preparation involved. i admit i have something of an obsession with renderman renderers, but i have yet to find a really reliable exporter for Blender, aside from the old MOSAIC one for Blender 2.49.
personally, i’m thinking of giving up entirely on renderman until i can save up ~$6000 to get maya and PRMan.
@ohsnapitsjoel 3Delight is free for two cores and Matt Ebb has a pretty good exporter going. 3Delight is a pretty good PRMan alternative.
Slight correction: renderman is a spec for a renderer. This is why there are several “renderman compliant” renderers.
yeah, but progress on that exporter has slowed, which is fine and understandable. reading some of his blog posts, looks like he keeps pretty busy with a personal life! some people seem to be able to get it working, but i’ve had very much varied success with that particular exporter, RIB Mosaic (which so far, for me at least, has been the most functional and least buggy exporter for 2.5x+) and frigge’s. functionality for these exporters always seems to hinge on blender/3Delight versions and revisions. i couldn’t get matt’s version 0.7 exporter to work at all with 3Delight 10.0.4, but i could (SOMETIMES) with 3Delight 9.x.x.
this is only my humble opinion - one needs to be a pretty proficient programmer to be able to get decent renderman functionality out of blender. i’m not one, unfortunately; i know nothing about programming 
i need out-of-the-box functionality. my two cents to anyone looking at a blender/renderman pipeline is to have a good programmer on board for your project.
I am aware that “renderman” is a renderer spec. At the same time though, Pixar calls its renderers for purchase “RenderMan for Maya”, “RenderMan Pro”, etc. I guess should have clarified that that was what I was referring to. 
Last version of aqsis was released recently.
http://www.blendertorenderman.org/2012/03/aqsis-18-released.html
Unfortunately, ribmosaic was not updated to work with 2.6.
I doubt a 3delight exporter is able to compile and launch an aqsis render.
Ribmosaic was able to render with several render engines in 2.4.
It inspires renderAPI but was updated to 2.5 when RenderAPI had few feaures.
I don’t think a ribmosaic exporter make sense, now.
But an aqsis exporter is needed.
It is the only FOSS renderman compliant renderer with an active development.
Free 3Delight licence is restricted to two cores.
You can use as many as you want with aqsis.
I think Matt’s exporter can work with Aqsis. The problem I had was with getting Aqsis to actually work that is why I just went with 3Delight, it worked out-of-the-box. Renderman, as a spec, is hard enough to get your head around along with having to get two systems to communicate for artists purposes.
If you have a link to the current version of Aqsis installer for WindowsXP64 I will give it a try. Try to see if I can get Matt’s exporter to launch Aqsis. The possibility of rendering with more cores is always attractive.
Thanks, nfz!
He made an update of ribmosaic, two hours ago.
Now, it works with 2.62.
Wow, where is the link? I was just looking at aqsis.org and gave up again.
That is what is so confusing about RIBMosaic. There is a big fat red sign on source forge that says to go to aqsis.org. But in the downloads section there is are no exporters at all.
If your using blender try vray, metal ray not working with blender, also render man costs 3500$, more then maya and a the same as 3d max.
Either, depending on the artist.
are you serious?? that’s awesome!
fyi, Atom: the latest release of Aqsis (1.8.1) binaries don’t install correctly on Windows. i can only use it on Ubuntu. i’m sure if you build from source, you can get it working, but i’m no good at compiling on Windows…
how? i compiled Aqsis on Ubuntu and tried to enable multithreading but i haven’t figured out how to get it to actually use more than one.
if i’m not mistaken, i believe Pixar calls its actual renderer PRMan (Photorealistic RenderMan).
I don’t think its ever been multi threaded
Hmm. That’s cool!
Yes, I know that is what the renderer program itself is actually called, but they sell it bundled with stuff as just plain RenderMan (Pixar Tools). Besides, adding “Photorealistic” before the name doesn’t really change the name. Whatever though, I think we all know what we all are revering to.