Ello,
I can't seem to find this node, Karma Physical Lens, is it not available for houdini Indie?
I searched in the stage, material library and shop context, tried also making a karma material subnetwork and I still couldnt find this node, has something changed for v20?

strange.. my camera in solaris, under the Karma tag, the settings are greyed out

I clicked this little icon next to the parameter and changed it to "set or create" and then i ticked "use Lens Shader" and now suddenly when I search for physical lens node it shows up in the material library context, maybe I changed something else? I dont know, but its showing up now

I am so confused, I am back in the material library, if I press Tab or right click, i cant find the physical shader node, but I do see it right there in my history from when I did get it to show up, which I dont know what I did to get it show before, whats going on?

It's probably a bit confusing when trying this for the first time.

You create the Karma Physical Lens not in a material library, but a Material Network.

So put down a material network on /stage or in your lopnet, dive inside, and then you can find it in the Tab-menu.

protozoan
It's probably a bit confusing when trying this for the first time.

You create the Karma Physical Lens not in a material library, but a Material Network.

So put down a material network on /stage or in your lopnet, dive inside, and then you can find it in the Tab-menu.

Ah I see, yes, I can see it now in the material network context thank you.
After having created the node, I see it as an option to create in the stage>material library node context in the history section when I press tab/right click, what is the difference between these contexts and should I stick to making my materials in the normal material network context? Is this an exception for the camera lens shader only?
Thank you for your help.

NNNenov
Ah I see, yes, I can see it now in the material network context thank you.
After having created the node, I see it as an option to create in the stage>material library node context in the history section when I press tab/right click, what is the difference between these contexts and should I stick to making my materials in the normal material network context? Is this an exception for the camera lens shader only?
Thank you for your help

Yes, stick to the material library for creating materials. The 'library' does the job of creating the USD layer from the nodes inside and adding it to the scene. A material network is just a place to put nodes. A material library can be used to translate the nodes which exist outside of itself, such as a material network, but it's more convenient to place nodes within.

A lens shader is not a material and exists outside of USD. Its implementation is somewhat of a 'hack' as it side steps translation.