Here's my feedback about the experience. I bet a lot of these are going to boil down to just stuff I don't know, but some may be genuine bugs or things that can be improved.
Preliminary verdict: working in Solaris was a pleasure and I didn't run into anything that I felt was missing or wished I could do but couldn't. I think once a few of my relatively minor concerns are addressed (Houdini 19 maybe?!) it will be my go-to renderer.
First, the render, then my comments below.
The Good
- It's really easy to bring geo in from /obj, including groups (via the name node) and vertex colors.
- It's simple to set up a very clear scene graph, cameras over here, geo over there, lights here, etc.
- It's great to have the viewport IPR, giving quick feedback when things are changed.
- I have a custom OCIO config (brian.ocio!) and Karma seemed to know what was up and I never had any colorspace issues.
- The camera focus visualizer is the greatest thing ever, even better with the OpenGL DoF approximation that you can turn on.
- The finished scene rendered super fast, only about 5min on my kind of old desktop (i7 something).
The Bad
- I originally had all my mats in material builders, but that seems to break updating the Karma IPR. Put a shader into a mat builder and no changes propagate up to Karma. You have to disconnect the shader from the collector and reconnect it for it to see the change. This is solved by not using mat builders, but then you get this big ol' mess.
- EDIT: Resolved this. I moved the matnet to the top of the tree and split up my material assignments per section of the model. Lag gone!
- I ran into trouble with my wings in that the principled shader doesn't have thin film. I ended up using the classic shader and it looks great, but it's a little odd that the "main" shader doesn't have that feature.
- Shader assignment gets more and more confusing as you add new ones. This list is so visually monolithic that it takes some real thinking to find what you're looking for. I suppose it would be possible to break it up across several nodes (wings, body, hair, etc), but still...
- Solaris is a little bit crashy. Not too much though, and honestly I feel like Arnold or Octane would have crashed a bunch too, so no big deal. But it did happen 5 or 6 times today.
The Ugly
- Render region in the image mode of the Karma IPR is broken. I submitted a bug report about it, but this makes it really really hard to fine tune individual areas. I couldn't look at just the eye since the ENTIRE thing had to keep rendering and it took forever to converge on the spot I was interested in. Render region worked way back in 18.0, but something broke over the last few months. MINI EDIT: There's a crop feature in the Karma properties that lets you zero in on a detail you want to work on. But, trying to guess a set of coordinates between 0,0 and 1,1 for the crop area is suboptimal. I'm definitely still looking for a real render region feature in the next update.
So there you go, just one ugly! All in all Solaris and Karma are very good and useable. I love that everything works as I expect and I can get EXACTLY the look I want. I didn't feel I was making any compromises. There is nothing in the finished scene that I feel would have looked better in Arnold.
It was a fun project and I'm excited to see what improvements SideFX is cooking up for the next release!