Currently there is no simple way to render left and right eye cameras for stereo. Note that the stereo pair does not require just a parallel offset to the left and right, but also a slight rotation about the vertical axis to converge at a finite distance, so creating that by hand is simply not an option.
We can imagine adding optional interocular distance and convergence distance parameters to the Animation Saver UI, so when you go to save an image sequence, you could save the original camera, Left Eye, Right Eye, both eyes, or all three views, and save them in one go, or in multiple save runs (saving all cameras in one go would be much faster because the points or meshes would be pre-loaded already for the central camera, so saving two more images would be just additional tasks to write files to disk). The image saving will be a lot faster in the upcoming v1.1, so that will help too.
Do you need to display all particles in C4D? The display is for preview purposes only, I would assume you could render left and right eye cameras in Krakatoa without crashing? If you need advice about rendering scanned data with Krakatoa without direct lighting, please let me know.
I cannot promise the Stereo camera feature will make it for your deadline, but I will talk to the developers tomorrow and see what we can do…
The latest Krakatoa C4D should read PLY files directly in the PRT Loader (I just tested it here and it works).
By default, the PRT Loader’s Display is limited to 1 million (1000x1000) particles. You can change the Display Load Mode to “Every Nth Particle” and enter a Percent Of Render Count value less than 100 (for example, 1) to show a fraction of the particles, while getting a good distribution to see where the particles are. By default the Display uses the Renderer’s mode, which is set to First N particles, so you cannot see the whole scan in that mode if the samples are ordered spatially. Note that the Renderer still defaults to 100% particles, so when you render, you should get all the millions of points.
To get the Color channel rendering without lighting, add a Krakatoa Channel Copy tag to the PRT Loader. Select Color as the Source Channel, and Emission as the Destination Channel (these are the defaults anyway).
Then in the Krakatoa setup, check “Ignore Scene Lights” and “Use Emission”. This should render the Color channel as Emission without any illumination.
You can then tweak the Final Pass Density value to get the density and intensity of the color low enough to produce smooth results, but high enough to see all the colors. The Final Pass Density and Exponent values work together, by default Final Pass Density 5 and Exponent -1 produce 5.0*10^-1 = 0.5. Changing the Exponent to -2 produces Final Pass Density of 0.05, -3 gives you 0.005 etc. So you can tweak both values until you like the look…