Hello again, I have a project where I need to render particles with a 180 degree spherical lens and stereoscopic. The Krakatoa camera modifier has a great spherical lens setup. The question is what kind of setup do I need to use to render it in stereo? Would a simple camera setup plugin work for this? I hope someone can help me with this.
Unfortunately there isn’t anything in Krakatoa itself to automatically handle stereo rendering at the moment. Of course, you could create a stereo camera rig with two or three cameras, and render a sequence from the left eye, and a sequence from the right eye (in fact, Deadline’s Submit Max To Deadline submitter supports that). However, it would be somewhat inefficient.
In theory, it would be nice if you could render the left and the right cameras out of PCache/LCache in one go, as it would mean that the loading of the frame’s particles, sorting for lights, and lighting would be performed only once, and then the camera sorting and drawing would be performed individually for each eye. Then you would release the caches, move to the next frame, and do the next frame the same way. This would save a lot of time.
Naturally, the above could be scripted. The main question is - do you want to render this on your workstation, or as a Deadline job? Depending on that, we could discuss different solutions…
If you want to use just Krakatoa as is, simply create two cameras linked to a dummy, add Krakatoa Camera modifiers, and render each one of them separately to its own sequence. It will take a bit longer as every frame of each eye will be loaded, lit, and rendered individually, but you wouldn’t have to wait for a scripted solution…
Thank you so much for the answer Bobo! I will probably use your technique rendering the particles to memory and than render the frames from there. But I even decided to render the lights to emmision so you dont have that problem. Works like a charm.
One more question; if you render the camera modifier with the settings, spherical lens and a fov of 180 degrees, you will get an image without a lens circle. I know if you rendered an image with the same settings in a older version of Krakatoa, you will get an sphere image.
Later in post, I need to convert the image to an equirectangular image. I noticed that a portion of the rendered image will be lost due to the conversion. But if you rendered it with a circle you wont have this problem.
So my question is, can I render the image with a circle? If so, will this speed up the render time?
The best way to produce a equirectangular (lat-long) projection is by rendering 6 x 90 degree views for each eye (cubic view), and then running a converter to turn those into lat-long.
The good news is that we had this implemented for Krakatoa MX 3.0. The bad news is we never released it 
We were matching the 6x1 strips of V-Ray.
Again, you could write a script to create and render 6 cameras per eye without any modifier, just 90 degrees FOV, rendering views in all 6 directions. You could then stack them into a single 6x1 strip using MAXScript.
I believe there are 3rd party tools out there that could take 6x1 cubic projections and create the equirectangular projection…