I also don't like Blender Render because of all the thousands of presets that do things I'm not accounting for. Basically, it's hard to use for just making a simple test scenes to render.
Thought you don't like blender, it comes to (my) mind first. Blender's cycle, starting with a simple diffuse only material and some light sources. It is a path tracer and should deliver a pretty solid GI solution.
That's true, blender cycles is really nice and easy to use, much less painful than normal blender render used to be.
Also, on the topic of physical based vs correctness, that's very true. The big thing for me, though, is having results that agree with everyone else's results.
Isn't POVRay a common choice for this sort of thing?
That's the crux of the matter, I don't know if it is or not. Thanks for the advice!
Arnold is very good, but also very not-free.
I've had some people recommend LuxRender, but I don't really have any experience with it myself.
Have you thought about writing a quick exporter tool to Mitsuba's file format? If you can do that, you can totally skip the pain of manually editing XML files. In fact I wasn't really advocating that you hand-write the XML in my blog post, I was just doing it as a way help familiarize people with the format and Mitsuba's functionality.
LuxRender looks fantastic, and Arnold looked amazing too in last year's SIGGRAPH!
The XML-exporting thing is a valid point, and it's something I could do. I've been using it to set up very simple scenes, so it doesn't matter too much as of right now, I was wondering for future alternatives. I'll look into LuxRender and POVRay though.
Regardless, if the hug variety of pathtracing programs out there really aren't to your liking you could practice and write your own, if it means that much to you.
Funny enough, I did, and I'm not sure if the results from my pathtracer are accurate either. Kind of a catch 22